In MONARCH 3, continuous dosing of abemaciclib with an aromatase inhibitor (AI) conferred significant clinical benefit to postmenopausal women with HR+, HER2- advanced breast cancer. We report data for clinically prognostic subgroups: liver metastases, progesterone receptor status, tumor grade, bone-only disease, ECOG performance status, and treatment-free interval (TFI) from an additional 12-month follow-up (after final progression-free survival [PFS] readout). In the intent-to-treat population, after median follow-up of approximately 39 months, the updated PFS was 28.2 versus 14.8 months (hazard ratio [HR], 0.525; 95% confidence interval, 0.415-0.665) in abemaciclib versus placebo arms, respectively. Time to chemotherapy (HR, 0.513), time to second disease progression (HR, 0.637), and duration of response (HR, 0.466) were also statistically significantly prolonged with the addition of abemaciclib to AI. Treatment benefit was observed across all subgroups, as evidenced by objective response rate change from the addition of abemaciclib to AI, with the largest effects observed in patients with liver metastases, progesterone receptor-negative tumors, high-grade tumors, or TFI < 36 months. Extended follow-up in the MONARCH 3 trial further confirmed that the addition of abemaciclib to AI conferred significant treatment benefit to all subgroups, including those with poorer prognosis..

PURPOSE: Palbociclib is approved in 1st line for hormone receptor (HR)-positive HER2-negative advanced breast cancer (ABC). A Compassionate Access Programme previously allowed patients to receive it in 4th line. However, Palbociclib has not been specifically tested in this population. We aimed to determine the safety and efficacy profile of Palbociclib within the Programme across ten institutions in the United Kingdom. METHODS: We retrospectively identified HR-positive HER2-negative ABC patients on the Programme between December 2015 and September 2017. Demographics, disease characteristics, prior treatments, blood tests, toxicities, treatment delays and responses were recorded. Simple statistics, Fisher's exact test, χ2 method and Cox regression were used. RESULTS: 118 patients identified had a median age of 59. 82.2% were postmenopausal and 92.4% performance status 0-1. 81.4% had visceral involvement and 6.8% bone-only disease after a median of 5 prior treatments and 3 prior chemotherapies. Clinical benefit rate was 47.5%, overall response rate 15.8%, median PFS 4.5 months and median OS 15.8 months. Longer progression-free survival on prior endocrine therapy was a predictor of longer PFS and OS. 89.7% developed neutropenia (grade ≥ 3 in 56.8%). 5.1% experienced febrile neutropenia. 48.3% had dose reductions and 3.4% discontinued Palbociclib following toxicity. No statistically significant difference in grade ≥ 3 neutropenia was observed according to metastatic sites nor previous treatments. CONCLUSIONS: This is the most extensive analysis of palbociclib in ≥ 4th-line setting. Clinical benefit was confirmed particularly for endocrine-sensitive, predominantly bony disease and in earlier lines of treatment. Safety was similar to PALOMA trials with higher febrile neutropenia rate..

Approximately 70% of breast cancers are estrogen-receptor positive. Tamoxifen and aromatase inhibitors have been the mainstay of endocrine therapy and have improved breast cancer survival. However, a large number of patients experience disease recurrence either during or following completion of endocrine therapy. Recent improvements in our understanding of the various mechanisms underlying the development of endocrine resistance have led to a dramatic change in the landscape of current endocrine treatment with the introduction of new drugs targeting molecular pathways involved in endocrine resistance. Over the past years we have witnessed the use of combination endocrine therapy with mammalian target of rapamycin antagonists, whilst most recently the introduction of cyclin-dependent kinase 4/6 inhibitors has significantly improved response to endocrine therapy. Whilst not a formal systematic review, this article will provide historical background and summarise key clinical trials and current strategies in both first-line and second-line endocrine therapy..

PURPOSE: CDK4/6 inhibitors are used to treat estrogen receptor (ER)-positive metastatic breast cancer (BC) in combination with endocrine therapy. PALLET is a phase II randomized trial that evaluated the effects of combination palbociclib plus letrozole as neoadjuvant therapy. PATIENTS AND METHODS: Postmenopausal women with ER-positive primary BC and tumors greater than or equal to 2.0 cm were randomly assigned 3:2:2:2 to letrozole (2.5 mg/d) for 14 weeks (A); letrozole for 2 weeks, then palbociclib plus letrozole to 14 weeks (B); palbociclib for 2 weeks, then palbociclib plus letrozole to 14 weeks (C); or palbociclib plus letrozole for 14 weeks. Palbociclib 125 mg/d was administered orally on a 21-days-on, 7-days-off schedule. Core-cut biopsies were taken at baseline and 2 and 14 weeks. Coprimary end points for letrozole versus palbociclib plus letrozole groups (A v B + C + D) were change in Ki-67 (protein encoded by the  MKI67 gene; immunohistochemistry) between baseline and 14 weeks and clinical response (ordinal and ultrasound) after 14 weeks. Complete cell-cycle arrest was defined as Ki-67 less than or equal to 2.7%. Apoptosis was characterized by cleaved poly (ADP-ribose) polymerase. RESULTS: Three hundred seven patients were recruited. Clinical response was not significantly different between palbociclib plus letrozole and letrozole groups ( P = .20; complete response + partial response, 54.3% v 49.5%), and progressive disease was 3.2% versus 5.4%, respectively. Median log-fold change in Ki-67 was greater with palbociclib plus letrozole compared with letrozole (-4.1 v -2.2; P < .001) in the 190 evaluable patients (61.9%), corresponding to a geometric mean change of -97.4% versus -88.5%. More patients on palbociclib plus letrozole achieved complete cell-cycle arrest (90% v 59%; P < .001). Median log-fold change (suppression) of cleaved poly (ADP-ribose) polymerase was greater with palbociclib plus letrozole versus letrozole (-0.80 v -0.42; P < .001). More patients had grade 3 or greater toxicity on palbociclib plus letrozole (49.8% v 17.0%; P < .001) mainly because of asymptomatic neutropenia. CONCLUSION: Adding palbociclib to letrozole significantly enhanced the suppression of malignant cell proliferation (Ki-67) in primary ER-positive BC, but did not increase the clinical response rate over 14 weeks, which was possibly related to a concurrent reduction in apoptosis..

At the MONARCH 3 interim analysis, abemaciclib plus a nonsteroidal aromatase inhibitor (AI) significantly improved progression-free survival (PFS) and objective response rate (ORR) with a tolerable safety profile as initial treatment for hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC). MONARCH 3 is a randomized, phase III, double-blind study of abemaciclib/placebo (150 mg twice daily, continuous) plus nonsteroidal AI (1 mg anastrozole or 2.5 mg letrozole, daily). A total of 493 postmenopausal women with HR+, HER2- ABC with no prior systemic therapy in this setting were enrolled. The primary endpoint was investigator-assessed PFS (final analysis after 240 events); other endpoints included response and safety evaluations. Here we analyze the final PFS data and update secondary endpoints. The abemaciclib arm had a significantly longer median PFS than the placebo arm (28.18 versus 14.76 months; hazard ratio [95% confidence interval], 0.540 [0.418-0.698]; p = .000002). The ORR was 61.0% in the abemaciclib arm versus 45.5% in the placebo arm (measurable disease, p = .003). The median duration of response was longer in the abemaciclib arm (27.39 months) compared to the placebo arm (17.46 months). The safety profile was consistent with previous reports. The most frequent grade ≥ 3 adverse events in the abemaciclib versus placebo arms were neutropenia (23.9% versus 1.2%), diarrhea (9.5% versus 1.2%), and leukopenia (8.6% versus 0.6%). Abemaciclib plus a nonsteroidal AI was an effective initial treatment with an acceptable safety profile for HR+, HER2- ABC..

BACKGROUND: Selection of resistance mutations may play a major role in the development of endocrine resistance. ESR1 mutations are rare in primary breast cancer but have high prevalence in patients treated with aromatase inhibitors (AI) for advanced breast cancer. We investigated the evolution of genetic resistance to the first-line AI therapy using sequential ctDNA sampling in patients with advanced breast cancer. PATIENTS AND METHODS: Eighty-three patients on the first-line AI therapy for metastatic breast cancer were enrolled in a prospective study. Plasma samples were collected every 3 months to disease progression and ctDNA analysed by digital droplet PCR and enhanced tagged-amplicon sequencing (eTAm-Seq). Mutations identified in progression samples by sequencing were tracked back through samples before progression to study the evolution of mutations on therapy. The frequency of novel mutations was validated in an independent cohort of available baseline plasma samples in the Study of Faslodex versus Exemestane with or without Arimidex (SoFEA) trial, which enrolled patients with prior sensitivity to AI. RESULTS: Of the 39 patients who progressed on the first-line AI, 56.4% (22/39) had ESR1 mutations detectable at progression, which were polyclonal in 40.9% (9/22) patients. In serial tracking, ESR1 mutations were detectable median 6.7 months (95% confidence interval 3.7-NA) before clinical progression. Utilising eTAm-Seq ctDNA sequencing of progression plasma, ESR1 mutations were demonstrated to be sub-clonal in 72.2% (13/18) patients. Mutations in RAS genes were identified in 15.4% (6/39) of progressing patients (4 KRAS, 1 HRAS, 1 NRAS). In SoFEA, KRAS mutations were detected in 21.2% (24/113) patients although there was no evidence that KRAS mutation status was prognostic for progression free or overall survival. CONCLUSIONS: Cancers progressing on the first-line AI show high levels of genetic heterogeneity, with frequent sub-clonal mutations. Sub-clonal KRAS mutations are found at high frequency. The genetic diversity of AI resistant cancers may limit subsequent targeted therapy approaches..

BACKGROUND: Activation of the PI3K/AKT/mTOR pathway occurs frequently in breast cancer that is resistant to endocrine therapy. Approved mTOR inhibitors effectively inhibit cell growth and proliferation but elicit AKT phosphorylation via a feedback activation pathway, potentially leading to resistance to mTOR inhibitors. We evaluated the efficacy and safety of buparlisib plus fulvestrant in patients with advanced breast cancer who were pretreated with endocrine therapy and mTOR inhibitors. METHODS: BELLE-3 was a randomised, double-blind, placebo-controlled, multicentre, phase 3 study. Postmenopausal women aged 18 years or older with histologically or cytologically confirmed hormone-receptor-positive, HER2-negative, locally advanced or metastatic breast cancer, who had relapsed on or after endocrine therapy and mTOR inhibitors, were recruited from 200 trial centres in 22 countries. Eligible patients were randomly assigned (2:1) via interactive response technology (block size of six) to receive oral buparlisib (100 mg per day) or matching placebo starting on day 1 of cycle 1, plus intramuscular fulvestrant (500 mg) on days 1 and 15 of cycle 1 and on day 1 of subsequent 28-day cycles. Randomisation was stratified by visceral disease status. The primary endpoint was progression-free survival by local investigator assessment as per the Response Evaluation Criteria In Solid Tumors (RECIST) version 1.1 in the full analysis population (all randomised patients, by intention-to-treat). Safety was analysed in all patients who received at least one dose of treatment and at least one post-baseline safety assessment. This study is registered with ClinicalTrials.gov, number NCT01633060, and is ongoing but no longer enrolling patients. FINDINGS: Between Jan 15, 2013, and March 31, 2016, 432 patients were randomly assigned to the buparlisib (n=289) or placebo (n=143) groups. Median progression-free survival was significantly longer in the buparlisib versus placebo group (3·9 months [95% CI 2·8-4·2] vs 1·8 months [1·5-2·8]; hazard ratio [HR] 0·67, 95% CI 0·53-0·84, one-sided p=0·00030). The most frequent grade 3-4 adverse events in the buparlisib versus placebo group were elevated alanine aminotransferase (63 [22%] of 288 patients vs four [3%] of 140), elevated aspartate aminotransferase (51 [18%] vs four [3%]), hyperglycaemia (35 [12%] vs none), hypertension (16 [6%] vs six [4%]), and fatigue (ten [3%] vs two [1%]). Serious adverse events were reported in 64 (22%) of 288 patients in the buparlisib group versus 23 (16%) of 140 in the placebo group; the most frequent serious adverse events (affecting ≥2% of patients) were elevated aspartate aminotransferase (six [2%] vs none), dyspnoea (six [2%] vs one [1%]), and pleural effusion (six [2%] vs none). On-treatment deaths occurred in ten (3%) of 288 patients in the buparlisib group and in six (4%) of 140 in the placebo group; most deaths were due to metastatic breast cancer, and two were considered treatment-related (cardiac failure [n=1] in the buparlisib group and unknown reason [n=1] in the placebo group). INTERPRETATION: The safety profile of buparlisib plus fulvestrant does not support its further development in this setting. Nonetheless, the efficacy of buparlisib supports the rationale for the use of PI3K inhibitors plus endocrine therapy in patients with PIK3CA mutations. FUNDING: Novartis Pharmaceuticals Corporation..

BACKGROUND: Patient-reported outcomes are integral in benefit-risk assessments of new treatment regimens. The PALOMA-2 study provides the largest body of evidence for patient-reported health-related quality of life (QOL) for patients with metastatic breast cancer (MBC) receiving first-line endocrine-based therapy (palbociclib plus letrozole and letrozole alone). PATIENTS AND METHODS: Treatment-naïve postmenopausal women with estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) MBC were randomized 2 : 1 to palbociclib plus letrozole (n = 444) or placebo plus letrozole (n = 222). Patient-reported outcomes were assessed at baseline, day 1 of cycles 2 and 3, and day 1 of every other cycle from cycle 5 using the Functional Assessment of Cancer Therapy (FACT)-Breast and EuroQOL 5 dimensions (EQ-5D) questionnaires. RESULTS: As of 26 February 2016, the median duration of follow-up was 23 months. Baseline scores were comparable between the two treatment arms. No significant between-arm differences were observed in change from baseline in FACT-Breast Total, FACT-General Total, or EQ-5D scores. Significantly greater improvement in pain scores was observed in the palbociclib plus letrozole arm (-0.256 versus -0.098; P = 0.0183). In both arms, deterioration of FACT-Breast Total score was significantly delayed in patients without progression versus those with progression and patients with partial or complete response versus those without. No significant difference was observed in FACT-Breast and EQ-5D index scores in patients with and without neutropenia. CONCLUSIONS: Overall, women with MBC receiving first-line endocrine therapy have a good QOL. The addition of palbociclib to letrozole maintains health-related QOL and improves pain scores in treatment-naïve postmenopausal patients with ER+/HER2- MBC compared with letrozole alone. Significantly greater delay in deterioration of health-related QOL was observed in patients without progression versus those who progressed and in patients with an objective response versus non-responders. ClinicalTrials.gov: NCT01740427 (https://clinicaltrials.gov/ct2/show/NCT01740427)..

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Ado-trastuzumab emtansine (T-DM1) is an antibody-drug conjugate that does not cross an intact blood-brain barrier. In the EMILIA trial of T-DM1 vs capecitabine/lapatinib for HER2 positive advanced breast cancer, all patients had baseline brain imaging, and 9/450 (2%) of patients with negative baseline imaging developed new brain disease during T-DM1. We assessed the frequency of brain progression in clinical practice, without routine baseline imaging. We undertook a retrospective study of all patients treated with T-DM1 at the Royal Marsden Hospital from 2011 to 2016. Data collected included baseline characteristics, previous treatment for advanced breast cancer, sites of metastatic disease, duration of T-DM1, sites of progression, and treatment of CNS progression. Fifty-five patients were identified who had received a median of two prior lines of treatment (range 0-5). All were HER2 positive; 45 patients had IHC 3+ tumors and 10 were ISH positive. Patients received a median of 12 cycles of T-DM1 (range 1-34), and six remain on treatment at the time of analysis. Before commencing T-DM1, 16/55 (29%) had known brain metastases (treated with whole brain [9] stereotactic radiotherapy [6] or both [1]). Brain was the first site of progression in 56% (9/16) patients, with a median time to brain progression of 9.9 months (95% CI 3.9-12.2). In patients without known baseline brain metastases, 17.9% (7/39) developed new symptomatic brain disease during T-DM1, after a median of 7.5 months (95%CI 3.8-9.6). Brain progression was isolated, with control of extra-cranial disease in 4/7 patients. Only one patient was suitable for stereotactic radiotherapy. Median time to extra-cranial progression in all patients was 11.5 months (95% CI 9.1-17.7), and median OS in all patients was 17.8 months (95% CI 14.2-22). In patients not screened for brain metastases at baseline, the brain was the first site of progression in a significant proportion. Baseline brain imaging may have a role in standard practice for patients commencing T-DM1 therapy..

Background: The objective of this study was to examine the presence and magnitude of US geographic variation in use rates of both recommended and high-cost imaging in young patients with early-stage breast cancer during the 18 month period after surgical treatment of their primary tumor. Methods: Using the Truven Health MarketScan Commercial Database, a descriptive analysis was conducted of geographic variation in annual rates of dedicated breast imaging and high-cost body imaging of 36,045 women aged 18 to 64 years treated with surgery for invasive unilateral breast cancer between 2010 and 2012. Multivariate hierarchical analysis examined the relationship between likelihood of imaging and patient characteristics, with metropolitan statistical area (MSA) serving as a random effect. Patient characteristics included age group, BRCA1/2 carrier status, family history of breast cancer, combination of breast surgery type and radiation therapy, drug therapy, and payer type. All MSAs in the United States were included, with areas outside MSAs within a given state aggregated into a single area for analytic purposes. Results: Descriptive analysis of rates of imaging use and intensity within MSA regions revealed wide geographic variation, irrespective of treatment cohort or age group. Increased probability of recommended postoperative dedicated breast imaging was primarily associated with age and treatment including both surgery and radiation therapy, followed by MSA region (odds ratio, 1.42). Increased probability of PET use-a high-cost imaging modality for which postoperative routine use is not recommended in the absence of specific clinical findings-was primarily associated with surgery type followed by MSA region (odds ratio, 1.82). Conclusions: In patients with breast cancer treated for low-risk disease, geography has effects on the rates of posttreatment imaging, suggesting that some patients are not receiving beneficial dedicated breast imaging, and high-cost nonbreast imaging may not be targeted to those groups most likely to benefit..

BACKGROUND: Resistance to endocrine therapy remains a major clinical problem in the treatment of oestrogen-receptor positive (ER+) breast cancer. Studies show androgen-receptor (AR) remains present in 80-90% of metastatic breast cancers providing support for blockade of AR-signalling. However, clinical studies with abiraterone, which blocks cytochrome P450 17A1 (CYP17A1) showed limited benefit. METHODS: In order to address this, we assessed the impact of abiraterone on cell-viability, cell-death, ER-mediated transactivation and recruitment to target promoters. together with ligand-binding assays in a panel of ER+ breast cancer cell lines that were either oestrogen-dependent, modelling endocrine-sensitive disease, or oestrogen-independent modelling relapse on an aromatase inhibitor. The latter, harboured wild-type (wt) or naturally occurring ESR1 mutations. RESULTS: Similar to oestrogen, abiraterone showed paradoxical impact on proliferation by stimulating cell growth or death, depending on whether the cells are hormone-dependent or have undergone prolonged oestrogen-deprivation, respectively. Abiraterone increased ER-turnover, induced ER-mediated transactivation and ER-degradation via the proteasome. CONCLUSIONS: Our study confirms the oestrogenic activity of abiraterone and highlights its differential impact on cells dependent on oestrogen for their proliferation vs. those that are ligand-independent and harbour wt or mutant ESR1. These properties could impact the clinical efficacy of abiraterone in breast cancer..

BACKGROUND: Endocrine therapies are the mainstay of treatment for oestrogen receptor (ER)-positive (ER+) breast cancer (BC). However, resistance remains problematic largely due to enhanced cross-talk between ER and growth factor pathways, circumventing the need for steroid hormones. Previously, we reported the anti-proliferative effect of everolimus (RAD001-mTORC1 inhibitor) with endocrine therapy in resistance models; however, potential routes of escape from treatment via ERBB2/3 signalling were observed. We hypothesised that combined targeting of three cellular nodes (ER, ERBB, and mTORC1) may provide enhanced long-term clinical utility. METHODS: A panel of ER+ BC cell lines adapted to long-term oestrogen deprivation (LTED) and expressing ESR1 wt or ESR1 Y537S , modelling acquired resistance to an aromatase-inhibitor (AI), were treated in vitro with a combination of RAD001 and neratinib (pan-ERBB inhibitor) in the presence or absence of oestradiol (E2), tamoxifen (4-OHT), or fulvestrant (ICI182780). End points included proliferation, cell signalling, cell cycle, and effect on ER-mediated transactivation. An in-vivo model of AI resistance was treated with monotherapies and combinations to assess the efficacy in delaying tumour progression. RNA-seq analysis was performed to identify changes in global gene expression as a result of the indicated therapies. RESULTS: Here, we show RAD001 and neratinib (pan-ERBB inhibitor) caused a concentration-dependent decrease in proliferation, irrespective of the ESR1 mutation status. The combination of either agent with endocrine therapy further reduced proliferation but the maximum effect was observed with a triple combination of RAD001, neratinib, and endocrine therapy. In the absence of oestrogen, RAD001 caused a reduction in ER-mediated transcription in the majority of the cell lines, which associated with a decrease in recruitment of ER to an oestrogen-response element on the TFF1 promoter. Contrastingly, neratinib increased both ER-mediated transactivation and ER recruitment, an effect reduced by the addition of RAD001. In-vivo analysis of an LTED model showed the triple combination of RAD001, neratinib, and fulvestrant was most effective at reducing tumour volume. Gene set enrichment analysis revealed that the addition of neratinib negated the epidermal growth factor (EGF)/EGF receptor feedback loops associated with RAD001. CONCLUSIONS: Our data support the combination of therapies targeting ERBB2/3 and mTORC1 signalling, together with fulvestrant, in patients who relapse on endocrine therapy and retain a functional ER..

AIM: Because incidence of breast cancer and comorbidities increase with age, it is important to determine treatment benefit in elderly patients. We evaluated outcomes with palbociclib plus endocrine therapy in patients aged ≥65 years. METHODS: Data were pooled from three randomised studies (NCT00721409, NCT01740427 and NCT01942135) of women with HR+/HER2- advanced breast cancer (ABC). In PALOMA-1 (open-label) and PALOMA-2 (double-blind, placebo-controlled), treatment-naïve patients received palbociclib plus letrozole or letrozole alone. In PALOMA-3 (double-blind, placebo-controlled), patients with endocrine-resistant disease received palbociclib plus fulvestrant or fulvestrant alone. RESULTS: Among 528 patients treated with palbociclib plus letrozole and 347 treated with palbociclib plus fulvestrant, 218 (41.3%) and 86 (24.8%), respectively, were aged ≥65 years. Versus endocrine therapy alone, median progression-free survival was significantly improved in patients aged 65-74 years (hazard ratio [HR], 0.66; 95% confidence interval [CI], 0.45-0.97; P = 0.016) and ≥75 years (HR, 0.31; 95% CI, 0.16-0.61; P<0.001) receiving palbociclib plus letrozole and in patients aged 65-74 years (HR, 0.27; 95% CI, 0.16-0.48; P<0.001) receiving palbociclib plus fulvestrant; few patients aged ≥75 years received palbociclib plus fulvestrant (HR, 0.59; 95% CI, 0.19-1.8; P = 0.18). Patient-reported functioning and quality of life was maintained. No clinically relevant differences in palbociclib exposure were observed between age groups. Although myelosuppression was more common among patients aged ≥75 years, incidence of grade ≥III myelosuppression was similar across age groups, and febrile neutropenia was uncommon (≤2.4%); no new safety concerns were identified in older patients. CONCLUSIONS: Palbociclib plus endocrine therapy is an effective, well-tolerated treatment for older patients with ABC..

Purpose Human epidermal growth factor receptor 2 (HER2) targeting plus endocrine therapy (ET) improved clinical benefit in HER2-positive, hormone receptor (HR)-positive metastatic breast cancer (MBC) versus ET alone. Dual HER2 blockade enhances clinical benefit versus single HER2 blockade. The ALTERNATIVE study evaluated the efficacy and safety of dual HER2 blockade plus aromatase inhibitor (AI) in postmenopausal women with HER2-positive/HR-positive MBC who received prior ET and prior neo(adjuvant)/first-line trastuzumab (TRAS) plus chemotherapy. Methods Patients were randomly assigned (1:1:1) to receive lapatinib (LAP) + TRAS + AI, TRAS + AI, or LAP + AI. Patients for whom chemotherapy was intended were excluded. The primary end point was progression-free survival (PFS; investigator assessed) with LAP + TRAS + AI versus TRAS + AI. Secondary end points were PFS (comparison of other arms), overall survival, overall response rate, clinical benefit rate, and safety. Results Three hundred fifty-five patients were included in this analysis: LAP + TRAS + AI (n = 120), TRAS + AI (n = 117), and LAP + AI (n = 118). Baseline characteristics were balanced. The study met its primary end point; superior PFS was observed with LAP + TRAS + AI versus TRAS + AI (median PFS, 11 v 5.7 months; hazard ratio, 0.62; 95% CI, 0.45 to 0.88; P = .0064). Consistent PFS benefit was observed in predefined subgroups. Overall response rate, clinical benefit rate, and overall survival also favored LAP + TRAS + AI. The median PFS with LAP + AI versus TRAS + AI was 8.3 versus 5.7 months (hazard ratio, 0.71; 95% CI, 0.51 to 0.98; P = .0361). Common adverse events (AEs; ≥ 15%) with LAP + TRAS + AI, TRAS + AI, and LAP + AI were diarrhea (69%, 9%, and 51%, respectively), rash (36%, 2%, and 28%, respectively), nausea (22%, 9%, and 22%, respectively), and paronychia (30%, 0%, and 15%, respectively), mostly grade 1 or 2. Serious AEs were reported similarly across the three groups, and AEs leading to discontinuation were lower with LAP + TRAS + AI. Conclusion Dual HER2 blockade with LAP + TRAS + AI showed superior PFS benefit versus TRAS + AI in patients with HER2-positive/HR-positive MBC. This combination offers an effective and safe chemotherapy-sparing alternative treatment regimen for this patient population..

INTRODUCTION: Phase I of the Cancer Research UK Stratified Medicine Programme (SMP1) was designed to roll out molecular pathology testing nationwide at the point of cancer diagnosis, as well as facilitate an infrastructure where surplus cancer tissue could be used for research. It offered a non-trial setting to examine common UK cancer genetics in a real-world context. METHODS: A total of 26 sites in England, Wales and Scotland, recruited samples from 7814 patients for genetic examination between 2011 and 2013. Tumour types involved were breast, colorectal, lung, prostate, ovarian cancer and malignant melanoma. Centralised molecular testing of surplus material from resections or biopsies of primary/metastatic tissue was performed, with samples examined for 3-5 genetic alterations deemed to be of key interest in site-specific cancers by the National Cancer Research Institute Clinical Study groups. RESULTS: 10 754 patients (98% of those approached) consented to participate, from which 7814 tumour samples were genetically analysed. In total, 53% had at least one genetic aberration detected. From 1885 patients with lung cancer, KRAS mutation was noted to be highly prevalent in adenocarcinoma (37%). In breast cancer (1873 patients), there was a striking contrast in TP53 mutation incidence between patients with ductal cancer (27.3%) and lobular cancer (3.4%). Vast inter-tumour heterogeneity of colorectal cancer (1550 patients) was observed, including myriad double and triple combinations of genetic aberrations. Significant losses of important clinical information included smoking status in lung cancer and loss of distinction between low-grade and high-grade serous ovarian cancers. CONCLUSION: Nationwide molecular pathology testing in a non-trial setting is feasible. The experience with SMP1 has been used to inform ongoing CRUK flagship programmes such as the CRUK National Lung MATRIX trial and TRACERx..

CDK4 & 6 inhibitors have enhanced the effectiveness of endocrine therapy (ET) in patients with advanced breast cancer (ABC). This paper presents exploratory analyses examining patient and disease characteristics that may inform in whom and when abemaciclib should be initiated. MONARCH 2 and 3 enrolled women with HR+, HER2- ABC. In MONARCH 2, patients whose disease had progressed while receiving ET were administered fulvestrant+abemaciclib/placebo. In MONARCH 3, patients received a nonsteroidal aromatase inhibitor+abemaciclib/placebo as initial therapy for advanced disease. A combined analysis of the two studies was performed to determine significant prognostic factors. Efficacy results (PFS and ORR in patients with measurable disease) were examined for patient subgroups corresponding to each significant prognostic factor. Analysis of clinical factors confirmed the following to have prognostic value: bone-only disease, liver metastases, tumor grade, progesterone receptor status, performance status, treatment-free interval (TFI) from the end of adjuvant ET, and time from diagnosis to recurrence. Prognosis was poorer in patients with liver metastases, progesterone receptor-negative tumors, high grade tumors, or short TFI (<36 months). Benefit (PFS hazard ratio, ORR increase) from abemaciclib was observed in all patient subgroups. Patients with indicators of poor prognosis had the largest benefit from the addition of abemaciclib. However, in MONARCH 3, for patients with certain good prognostic factors (TFI ≥ 36 months, bone-only disease) ET achieved a median PFS of >20 months. These analyses identified prognostic factors and demonstrated that patients with poor prognostic factors derived the largest benefit from the addition of abemaciclib..

AIMS: To determine whether IHC4 score assessed on pre-treatment core biopsies (i) predicts response to neo-adjuvant chemotherapy in ER-positive (ER+) breast cancer; (ii) provides more predictive information than Ki67 alone. METHODS: 113 patients with ER+ primary breast cancer treated with neo-adjuvant chemotherapy at the Royal Marsden Hospital between 2002 and 2010 were included in the study. Pathologic assessment of the excision specimen was made for residual disease. IHC4 was determined on pre-treatment core biopsies, blinded to clinical outcome, by immunohistochemistry using quantitative scoring of ER (H-score), PgR (%) and Ki67 (%). Determination of HER2 status was made by immunohistochemistry and fluorescent in situ hybridization for 2+ cases. IHC4 and Ki67 scores were tested for their association with pathological complete response (pCR) rate and residual cancer burden (RCB) score. RESULTS: 18 (16%) of the 113 patients and 8 (9%) of the 88 HER2-ve cases achieved pCR. Ki67 and IHC4 score were both positively associated with achievement of pCR (P < 10-7 and P < 10-9, respectively) and RCB0+1 (P < 10-5 and P < 10-9, respectively) following neo-adjuvant chemotherapy in all patients. Rates of pCR+RCB1 were 45 and 66% in the highest quartiles of Ki67 and IHC4 scores, respectively. In ER+HER2-ve cases, pCR+RCB1 rates were 35% and in the highest quartile of both Ki67 and IHC4. There were no pCRs in the lower half of IHC4 or Ki67 scores. CONCLUSIONS: IHC4 was strongly predictive of pCR or near pCR in ER+ breast cancers following neo-adjuvant chemotherapy. Ki67 was an important component of this predictive ability, but was not as predictive as IHC4..

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PURPOSE: Leptomeningeal disease (LMD) is an uncommon complication of advanced breast cancer. The prognosis is poor, and although radiotherapy (RT), systemic and intra-thecal (IT) chemotherapy are accepted treatment modalities, efficacy data are limited. This study was designed to evaluate potential predictors of survival in this patient group. METHODS: Breast cancer patients with LMD diagnosed by MRI in a 10-year period (2004-2014) were identified from electronic patient records. PFS and OS estimates were calculated using Kaplan-Meier method, with planned sub-group analysis by treatment modality. Cox regression was employed to identify significant prognostic variables. RESULTS: We identified 182 eligible patients; all female, median age at LMD diagnosis 52.5 years (range 23-80). Ninety patients (49.5%) were ER positive/HER2 negative; 48 (26.4%) were HER2 positive, and 27 (14.8%) were triple negative. HER2 status was unknown in 17 (9.3%). Initial management of LMD was most commonly whole or partial brain RT in 62 (34.1%), systemic therapy in 45 (24.7%) or supportive care alone in 37 (20.3%). Fourteen patients (7.7%) underwent IT chemotherapy, of whom two also received IT trastuzumab. From diagnosis of LMD, the median PFS was 3.9 months (95%CI 3.2-5.0) and median OS was 5.4 months (95%CI 4.2-6.6). Patients treated with systemic therapy had the longest OS (median 8.8 months, 95%CI 5.5-11.1), compared to RT; 6.1 months (95%CI 4.2-7.9 months), IT therapy; 2.9 months (95%CI 1.2-5.8) and supportive care; 1.7 months (95%CI 0.9-3.0). On multivariable analysis, triple negative histology, concomitant brain metastases, and LMD involving both the brain and spinal cord were associated with poor OS. CONCLUSIONS: Breast cancer patients with triple negative LMD, concomitant brain metastases or LMD affecting both the spine and brain have the poorest prognosis. Clinical trials to identify more effective treatments for these patients are urgently needed..

PURPOSE: To develop recommendations about endocrine therapy for women with hormone receptor (HR) -positive metastatic breast cancer (MBC). METHODS: The American Society of Clinical Oncology convened an Expert Panel to conduct a systematic review of evidence from 2008 through 2015 to create recommendations informed by that evidence. Outcomes of interest included sequencing of hormonal agents, hormonal agents compared with chemotherapy, targeted biologic therapy, and treatment of premenopausal women. This guideline puts forth recommendations for endocrine therapy as treatment for women with HR-positive MBC. RECOMMENDATIONS: Sequential hormone therapy is the preferential treatment for most women with HR-positive MBC. Except in cases of immediately life-threatening disease, hormone therapy, alone or in combination, should be used as initial treatment. Patients whose tumors express any level of hormone receptors should be offered hormone therapy. Treatment recommendations should be based on type of adjuvant treatment, disease-free interval, and organ function. Tumor markers should not be the sole criteria for determining tumor progression; use of additional biomarkers remains experimental. Assessment of menopausal status is critical; ovarian suppression or ablation should be included in premenopausal women. For postmenopausal women, aromatase inhibitors (AIs) are the preferred first-line endocrine therapy, with or without the cyclin-dependent kinase inhibitor palbociclib. As second-line therapy, fulvestrant should be administered at 500 mg with a loading schedule and may be administered with palbociclib. The mammalian target of rapamycin inhibitor everolimus may be administered with exemestane to postmenopausal women with MBC whose disease progresses while receiving nonsteroidal AIs. Among patients with HR-positive, human epidermal growth factor receptor 2-positive MBC, human epidermal growth factor receptor 2-targeted therapy plus an AI can be effective for those who are not chemotherapy candidates..

IMPORTANCE: The value of the intrinsic subtypes of breast cancer (luminal A, luminal B, human epidermal growth factor receptor 2 [currently known as ERBB2, but referred to as HER2 in this study]-enriched, and basal-like) in the metastatic setting is currently unknown. OBJECTIVE: To evaluate the association of the intrinsic subtypes of breast cancer with outcome and/or benefit in hormone receptor (HR)-positive metastatic breast cancer. DESIGN, SETTING, AND PARTICIPANTS: Unplanned retrospective analysis of 821 tumor samples (85.7% primary and 14.3% metastatic) from the EGF30008 phase 3 clinical trial (NCT00073528), in which postmenopausal women with HR-positive invasive breast cancer and no prior therapy for advanced or metastatic disease were randomized to letrozole with or without lapatinib, an epidermal growth factor receptor (EGFR)/HER2 tyrosine kinase inhibitor. Tumor samples were classified into each subtype using the research-based PAM50 classifier. Prior neoadjuvant/adjuvant antiestrogen therapy was allowed. Patients with extensive symptomatic visceral disease were excluded. Treatment effects were evaluated using interaction tests. MAIN OUTCOMES AND MEASURES: Primary and secondary end points were progression-free survival and overall survival. RESULTS: The median (range) age was 62 (31-94) years. Intrinsic subtype was the strongest prognostic factor independently associated with progression-free survival and overall survival in all patients, and in patients with HER2-negative (n = 644) or HER2-positive (n = 157) diseases. Median progression-free survival differed across the intrinsic subtypes of clinically HER2-negative disease: luminal A (16.9 [95% CI, 14.1-19.9] months), luminal B (11.0 [95% CI, 9.6-13.6] months), HER2-enriched (4.7 [95% CI, 2.7-10.8] months), and basal-like (4.1 [95% CI, 2.5-13.8] months). Median OS also differed across the intrinsic subtypes: luminal A (45 [95% CI, 41-not applicable {NA}] months), luminal B (37 [95% CI, 31-42] months), HER2-enriched (16 [95% CI, 10-NA] months), and basal-like (23 [95% CI, 12-NA] months). Patients with HER2-negative/HER2-enriched disease benefited from lapatinib therapy (median PFS, 6.49 vs 2.60 months; progression-free survival hazard ratio, 0.238 [95% CI, 0.066-0.863]; interaction P = .02). CONCLUSIONS AND RELEVANCE: This is the first study to reveal an association between intrinsic subtype and outcome in first-line HR-positive metastatic breast cancer. Patients with HR-positive/HER2-negative disease with a HER2-enriched profile may benefit from lapatinib in combination with endocrine therapy. The clinical value of intrinsic subtyping in hormone receptor-positive metastatic breast cancer warrants further investigation, but patients with luminal A/HER2-negative metastatic breast cancer might be good candidates for letrozole monotherapy in the first-line setting regardless of visceral disease and number of metastases..

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BACKGROUND: Androgen receptor (AR) signaling and incomplete inhibition of estrogen signaling may contribute to metastatic breast cancer (MBC) resistance to a nonsteroidal aromatase inhibitor (NSAI; letrozole or anastrozole). We assessed whether combined inhibition of androgen biosynthesis with abiraterone acetate plus prednisone and estradiol synthesis with exemestane (E) may be of clinical benefit to postmenopausal patients with NSAI-pretreated estrogen receptor-positive (ER+) MBC. PATIENTS AND METHODS: Patients (N = 297) were stratified by the number of prior therapies for metastatic disease (0-1 versus 2) and by prior NSAI use (adjuvant versus metastatic), and randomized (1 : 1 : 1) to receive oral once daily 1000 mg abiraterone acetate plus 5 mg prednisone (AA) versus AA with 25 mg E (AAE) versus 25 mg E alone (E). Each treatment arm was well balanced with regard to the proportion of patients with AR-positive breast cancer. The primary end point was progression-free survival (PFS). Secondary end points included overall survival, clinical benefit rate, duration of response, and overall response rate. RESULTS: There was no significant difference in PFS with AA versus E (3.7 versus 3.7 months; hazard ratio [HR] = 1.1; 95% confidence interval [CI] 0.82-1.60; P = 0.437) or AAE versus E (4.5 versus 3.7 months; HR = 0.96; 95% CI 0.70-1.32; P = 0.794). Increased serum progesterone concentrations were observed in both arms receiving AA, but not with E. Grade 3 or 4 treatment-emergent adverse events associated with AA, including hypokalemia and hypertension, were less common in patients in the E (2.0% and 2.9%, respectively) and AA arms (3.4% and 1.1%, respectively) than in the AAE arm (5.8% for both). CONCLUSIONS: Adding AA to E in NSAI-pretreated ER+ MBC patients did not improve PFS compared with treatment with E. An AA-induced progesterone increase may have contributed to this lack of clinical activity. CLINICALTRIALSGOV: NCT01381874..

BACKGROUND: The gold standard end point in randomized clinical trials in metastatic breast cancer (MBC) is overall survival (OS). Although therapeutics have been approved based on progression-free survival (PFS), its use as a primary end point is controversial. We aimed to assess to what extent PFS may be used as a surrogate for OS in randomized trials of anti-HER2 agents in HER2+ MBC. METHODS: Eligible trials accrued HER2+ MBC patients in 1992-2008. A correlation approach was used: at the individual level, to estimate the association between investigator-assessed PFS and OS using a bivariate model and at the trial level, to estimate the association between treatment effects on PFS and OS. Correlation values close to 1.0 would indicate strong surrogacy. RESULTS: We identified 2545 eligible patients in 13 randomized trials testing trastuzumab or lapatinib. We collected individual patient data from 1963 patients and retained 1839 patients from 9 trials for analysis (7 first-line trials). During follow-up, 1072 deaths and 1462 progression or deaths occurred. The median survival time was 22 months [95% confidence interval (CI) 21-23 months] and the median PFS was 5.7 months (95% CI 5.5-6.1 months). At the individual level, the Spearman correlation was equal to ρ = 0.67 (95% CI 0.66-0.67) corresponding to a squared correlation value of 0.45. At the trial level, the squared correlation between treatment effects (log hazard ratios) on PFS and OS was provided by R(2) = 0.51 (95% CI 0.22-0.81). CONCLUSIONS: In trials of HER2-targeted agents in HER2+ MBC, PFS moderately correlates with OS at the individual level and treatment effects on PFS correlate moderately with those on overall mortality, providing only modest support for considering PFS as a surrogate. PFS does not completely substitute for OS in this setting..

BACKGROUND: Inhibition of phosphatidylinositol 3-kinase (PI3K) is a promising approach to overcome resistance to endocrine therapy in breast cancer. Pictilisib is an oral inhibitor of multiple PI3K isoforms. The aim of this study is to establish if addition of pictilisib to fulvestrant can improve progression-free survival in oestrogen receptor-positive, endocrine-resistant breast cancer. METHODS: In this two-part, randomised, double-blind, placebo-controlled, phase 2 study, we recruited postmenopausal women aged 18 years or older with oestrogen receptor-positive, HER2-negative breast cancer resistant to treatment with an aromatase inhibitor in the adjuvant or metastatic setting, from 123 medical centres across 21 countries. Part 1 included patients with or without PIK3CA mutations, whereas part 2 included only patients with PIK3CA mutations. Patients were randomly allocated (1:1 in part 1 and 2:1 in part 2) via a computer-generated hierarchical randomisation algorithm to daily oral pictilisib (340 mg in part 1 and 260 mg in part 2) or placebo starting on day 15 of cycle 1, plus intramuscular fulvestrant 500 mg on day 1 and day 15 of cycle 1 and day 1 of subsequent cycles in both groups. In part 1, we stratified patients by presence or absence of PIK3CA mutation, primary or secondary aromatase inhibitor resistance, and measurable or non-measurable disease. In part 2, we stratified patients by previous aromatase inhibitor treatment for advanced or metastatic disease or relapse during or within 6 months of an aromatase inhibitor treatment in the adjuvant setting and measurable or non-measurable disease. All patients and those administering treatment and assessing outcomes were masked to treatment assignment. The primary endpoint was progression-free survival in the intention-to-treat population for both parts 1 and 2 and also separately in patients with PIK3CA-mutated tumours in part 1. Tumour assessment (physical examination and imaging scans) was investigator-assessed and done at screening and after 8 weeks, 16 weeks, 24 weeks, and 32 weeks of treatment from day 1 of cycle 1 and every 12 weeks thereafter. We assessed safety in as-treated patients who received at least one dose of study medication. This trial is registered with ClinicalTrials.gov, number NCT01437566. FINDINGS: In part 1, between Sept 27, 2011, and Jan 11, 2013, we randomly allocated 168 patients to the pictilisib (89 [53%]) or placebo (79 [47%]) group. In part 2, between March 18, 2013, and Jan 2, 2014, we randomly allocated 61 patients to the pictilisib (41 [67%]) or placebo (20 [33%]) group. In part 1, we found no difference in median progression-free survival between the pictilisib (6·6 months [95% CI 3·9-9·8]) and placebo (5·1 months [3·6-7·3]) group (hazard ratio [HR] 0·74 [95% CI 0·52-1·06]; p=0·096). We also found no difference when patients were analysed according to presence (pictilisib 6·5 months [95% CI 3·7-9·8] vs placebo 5·1 months [2·6-10·4]; HR 0·73 [95% CI 0·42-1·28]; p=0·268) or absence (5·8 months [3·6-11·1] vs 3·6 months [2·8-7·3]; HR 0·72 [0·42-1·23]; p=0·23) of PIK3CA mutation. In part 2, we also found no difference in progression-free survival between groups (5·4 months [95% CI 3·8-8·3] vs 10·0 months [3·6-13·0]; HR 1·07 [95% CI 0·53-2·18]; p=0·84). In part 1, grade 3 or worse adverse events occurred in 54 (61%) of 89 patients in the pictilisib group and 22 (28%) of 79 in the placebo group. 19 serious adverse events related to pictilisib treatment were reported in 14 (16%) of 89 patients. Only one (1%) of 79 patients reported treatment-related serious adverse events in the placebo group. In part 2, grade 3 or worse adverse events occurred in 15 (36%) of 42 patients in the pictilisib group and seven (37%) of 19 patients in the placebo group. Four serious adverse events related to pictilisib treatment were reported in two (5%) of 42 patients. One treatment-related serious adverse event occurred in one (5%) of 19 patients in the placebo group. INTERPRETATION: Although addition of pictilisib to fulvestrant did not significantly improve progression-free survival, dosing of pictilisib was limited by toxicity, potentially limiting its efficacy. For future assessment of PI3K inhibition as an approach to overcome resistance to hormonal therapy, inhibitors with greater selectivity than that of pictilisib might be needed to improve tolerability and potentially increase efficacy. No further investigation of pictilisib in this setting is ongoing. FUNDING: F Hoffmann-La Roche..

UNLABELLED: FGFR1 and FGFR2 are amplified in many tumor types, yet what determines response to FGFR inhibition in amplified cancers is unknown. In a translational clinical trial, we show that gastric cancers with high-level clonal FGFR2 amplification have a high response rate to the selective FGFR inhibitor AZD4547, whereas cancers with subclonal or low-level amplification did not respond. Using cell lines and patient-derived xenograft models, we show that high-level FGFR2 amplification initiates a distinct oncogene addiction phenotype, characterized by FGFR2-mediated transactivation of alternative receptor kinases, bringing PI3K/mTOR signaling under FGFR control. Signaling in low-level FGFR1-amplified cancers is more restricted to MAPK signaling, limiting sensitivity to FGFR inhibition. Finally, we show that circulating tumor DNA screening can identify high-level clonally amplified cancers. Our data provide a mechanistic understanding of the distinct pattern of oncogene addiction seen in highly amplified cancers and demonstrate the importance of clonality in predicting response to targeted therapy. SIGNIFICANCE: Robust single-agent response to FGFR inhibition is seen only in high-level FGFR-amplified cancers, with copy-number level dictating response to FGFR inhibition in vitro, in vivo, and in the clinic. High-level amplification of FGFR2 is relatively rare in gastric and breast cancers, and we show that screening for amplification in circulating tumor DNA may present a viable strategy to screen patients. Cancer Discov; 6(8); 838-51. ©2016 AACR.This article is highlighted in the In This Issue feature, p. 803..

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PURPOSE: AZD8931 is an orally bioavailable, reversible tyrosine kinase inhibitor of EGFR, HER2, and HER3 signaling. The Phase II MINT study (ClinicalTrials.gov NCT01151215) investigated whether adding AZD8931 to endocrine therapy would delay development of endocrine resistance in patients with hormone-sensitive advanced breast cancer. METHODS: Patients were randomized 1:1:1 to receive daily anastrozole (1 mg) in combination with AZD8931 20 mg twice daily (bid), AZD8931 40 mg bid, or placebo. The primary objective was evaluation of progression-free survival (PFS) in patients treated with combination AZD8931 and anastrozole versus anastrozole alone. Secondary objectives included assessment of safety and tolerability, objective response rate, and overall survival. RESULTS: At the interim analysis, 359 patients were randomized and received anastrozole in combination with AZD8931 20 mg (n = 118), 40 mg (n = 120), or placebo (n = 121); 39 % of patients (n = 141) had a progression event. Median PFS (HR; 95 % CI vs placebo) in the AZD8931 20, 40 mg, and placebo arms was 10.9 (1.37; 0.91-2.06, P = 0.135), 13.8 (1.16; 0.77-1.75, P = 0.485), and 14.0 months, respectively. No indication of clinical benefit was observed following treatment with AZD8931 for the secondary endpoints. Safety findings showed a greater incidence of diarrhea (40, 51, and 12 % for AZD8931 20, 40 mg, and placebo, respectively), rash (32, 48, and 12 %), dry skin (19, 25, and 2 %), and acneiform dermatitis (16, 28, and 2 %) in patients treated with AZD8931 versus placebo. CONCLUSIONS: AZD8931, in combination with endocrine therapy, does not appear to enhance endocrine responsiveness and is associated with greater skin and gastrointestinal toxicity..

BACKGROUND: Inflammatory breast cancer (IBC) is a rare, aggressive form of breast cancer associated with HER2 amplification, with high risk of metastasis and an estimated median survival of 2.9 y. We performed an open-label, single-arm phase II clinical trial (ClinicalTrials.gov NCT01325428) to investigate the efficacy and safety of afatinib, an irreversible ErbB family inhibitor, alone and in combination with vinorelbine in patients with HER2-positive IBC. This trial included prospectively planned exome analysis before and after afatinib monotherapy. METHODS AND FINDINGS: HER2-positive IBC patients received afatinib 40 mg daily until progression, and thereafter afatinib 40 mg daily and intravenous vinorelbine 25 mg/m2 weekly. The primary endpoint was clinical benefit; secondary endpoints were objective response (OR), duration of OR, and progression-free survival (PFS). Of 26 patients treated with afatinib monotherapy, clinical benefit was achieved in 9 patients (35%), 0 of 7 trastuzumab-treated patients and 9 of 19 trastuzumab-naïve patients. Following disease progression, 10 patients received afatinib plus vinorelbine, and clinical benefit was achieved in 2 of 4 trastuzumab-treated and 0 of 6 trastuzumab-naïve patients. All patients had treatment-related adverse events (AEs). Whole-exome sequencing of tumour biopsies taken before treatment and following disease progression on afatinib monotherapy was performed to assess the mutational landscape of IBC and evolutionary trajectories during therapy. Compared to a cohort of The Cancer Genome Atlas (TCGA) patients with HER2-positive non-IBC, HER2-positive IBC patients had significantly higher mutational and neoantigenic burden, more frequent gain-of-function TP53 mutations and a recurrent 11q13.5 amplification overlapping PAK1. Planned exploratory analysis revealed that trastuzumab-naïve patients with tumours harbouring somatic activation of PI3K/Akt signalling had significantly shorter PFS compared to those without (p = 0.03). High genomic concordance between biopsies taken before and following afatinib resistance was observed with stable clonal structures in non-responding tumours, and evidence of branched evolution in 8 of 9 tumours analysed. Recruitment to the trial was terminated early following the LUX-Breast 1 trial, which showed that afatinib combined with vinorelbine had similar PFS and OR rates to trastuzumab plus vinorelbine but shorter overall survival (OS), and was less tolerable. The main limitations of this study are that the results should be interpreted with caution given the relatively small patient cohort and the potential for tumour sampling bias between pre- and post-treatment tumour biopsies. CONCLUSIONS: Afatinib, with or without vinorelbine, showed activity in trastuzumab-naïve HER2-positive IBC patients in a planned subgroup analysis. HER2-positive IBC is characterized by frequent TP53 gain-of-function mutations and a high mutational burden. The high mutational load associated with HER2-positive IBC suggests a potential role for checkpoint inhibitor therapy in this disease. TRIAL REGISTRATION: ClinicalTrials.gov NCT01325428..

Mutations in ESR1 have been associated with resistance to aromatase inhibitor (AI) therapy in patients with ER+ metastatic breast cancer. Little is known of the impact of these mutations in patients receiving selective oestrogen receptor degrader (SERD) therapy. In this study, hotspot mutations in ESR1 and PIK3CA from ctDNA were assayed in clinical trial samples from ER+ metastatic breast cancer patients randomized either to the SERD fulvestrant or fulvestrant plus a pan-PI3K inhibitor. ESR1 mutations are present in 37% of baseline samples and are enriched in patients with luminal A and PIK3CA-mutated tumours. ESR1 mutations are often polyclonal and longitudinal analysis shows distinct clones exhibiting divergent behaviour over time. ESR1 mutation allele frequency does not show a consistent pattern of increases during fulvestrant treatment, and progression-free survival is not different in patients with ESR1 mutations compared with wild-type patients. ESR1 mutations are not associated with clinical resistance to fulvestrant in this study..

PURPOSE: Abiraterone may suppress androgens that stimulate breast cancer growth. We conducted a biomarker analysis of circulating tumor cells (CTCs), formalin-fixed paraffin-embedded tissues (FFPETs), and serum samples from postmenopausal estrogen receptor (ER)+ breast cancer patients to identify subgroups with differential abiraterone sensitivity. METHODS: Patients (randomized 1:1:1) were treated with 1,000 mg/d abiraterone acetate + 5 mg/d prednisone (AA), AA + 25 mg/d exemestane (AAE), or exemestane. The biomarker population included treated patients (n = 293). The CTC population included patients with ≥3 baseline CTCs (n = 104). Biomarker [e.g., androgen receptor (AR), ER, Ki-67, CYP17] expression was evaluated. Cox regression stratified by prior therapies in the metastatic setting (0/1 vs. 2) and setting of letrozole/anastrozole (adjuvant vs. metastatic) was used to assess biomarker associations with progression-free survival (PFS). RESULTS: Serum testosterone and estrogen levels were lowered and progesterone increased with AA. Baseline AR or ER expression was not associated with PFS in CTCs or FFPETs for AAE versus exemestane, but dual positivity of AR and ER expression was associated with improved PFS [HR, 0.41; 95% confidence interval (CI), 0.16-1.07; P = 0.070]. For AR expression in FFPETs obtained <1 year prior to first dose (n = 67), a trend for improved PFS was noted for AAE versus exemestane (HR, 0.56; 95% CI, 0.24-1.33; P = 0.19). CONCLUSIONS: An AA pharmacodynamic effect was shown by decreased serum androgen and estrogen levels and increased progesterone. AR and ER dual expression in CTCs and newly obtained FFPETs may predict AA sensitivity. Clin Cancer Res; 22(24); 6002-9. ©2016 AACR..

PURPOSE: We examined the prognostic and predictive value of serum human epidermal growth factor 2 (HER2) extracellular domain (sHER2) in patients with advanced breast cancer treated with lapatinib using data from three randomized trials. PATIENTS AND METHODS: We analyzed sHER2 and tissue HER2 (tHER2) data from 1,902 patients (84%) who were randomly assigned to receive lapatinib or control in the trials EGF30001, EGF30008, and EGF100151. Cox regression analyses were performed to correlate both biomarkers with progression-free survival (PFS) and overall survival (OS). RESULTS: Median sHER2 levels were 25.1 and 10.1 ng/mL in tHER2-amplified (tHER-positive) and nonamplified (tHER-negative) populations, respectively (r = 0.42 for sHER2-tHER2 correlation). Lapatinib had significant PFS benefit over control (hazard ratio [HR], 0.855; P = .004), but not OS (HR, 0.941; P = .33). Lapatinib PFS benefit is independently predicted by higher sHER2 values (HR per 10-ng/mL increase in sHER2: lapatinib-containing therapies, 1.009 v nonlapatinib-containing therapies, 1.044; P(interaction) < .001) and by positive tHER2 (HR [lapatinib v nonlapatinib]: tHER2 positive, 0.638 v tHER2 negative, 0.940; P(interaction) = .001). Within the tHER2-positive subpopulation (n = 515), higher sHER2 values still independently predicted lapatinib PFS benefit (HR per 10-ng/mL increase in sHER2: lapatinib-containing therapies, 1.017 v nonlapatinib-containing therapies, 1.041; P(interaction) = .008). In control arms (n = 936), higher sHER2 was associated with worse prognosis in multivariable analyses (PFS HR per 10 ng/mL: PFS, 1.024; P < .001; and OS, 1.018; P < .001). CONCLUSION: Higher sHER2 predicts greater PFS benefit with lapatinib independent of tHER2 status. High sHER2 is also independently prognostic for worse survival in patients who received nonlapatinib-containing therapies. The predictive role of sHER2 for other anti-HER2 agents requires further research..

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Despite the effectiveness of endocrine therapies in estrogen receptor positive (ER+) breast cancer, approximately 40% of patients relapse. Previously, we identified the Focal-adhesion kinase canonical pathway as a major contributor of resistance to estrogen deprivation and cellular-sarcoma kinase (c-src) as a dominant gene in this pathway. Dasatinib, a pan-src inhibitor, has recently been used in clinical trials to treat ER+ patients but has shown mixed success. In the following study, using isogenic cell line models, we provide a potential explanation for these findings and suggest a sub-group that may benefit. A panel of isogenic cell lines modelling resistance to aromatase inhibitors (LTED) and tamoxifen (TAMR) were assessed for response to dasatinib ± endocrine therapy. Dasatinib caused a dose-dependent decrease in proliferation in MCF7-TAMR cells and resensitized them to tamoxifen and fulvestrant but not in HCC1428-TAMR. In contrast, in estrogen-deprived conditions, dasatinib increased the proliferation rate of parental-MCF7 cells and had no effect on MCF7-LTED or HCC1428-LTED. Treatment with dasatinib caused a decrease in src-phosphorylation and inhibition of downstream pathways, including AKT and ERK1/2 in all cell lines tested, but only the MCF7-TAMR showed a concomitant decrease in markers of cell cycle progression. Inhibition of src also caused a significant decrease in cell migration in both MCF7-LTED and MCF7-TAMR cells. Finally, we showed that, in MCF7-TAMR cells, in contrast to tamoxifen sensitive cell lines, ER is expressed throughout the cell rather than being restricted to the nucleus and that treatment with dasatinib resulted in nuclear shuttling of ER, which was associated with an increase in ER-mediated transcription. These data suggest that src has differential effects in endocrine-resistant cell lines, particularly in tamoxifen resistant models, with low ER genomic activity, providing further evidence of the importance of patient selection for clinical trials testing dasatinib utility in ER+ breast cancer..

BACKGROUND: The purpose of this study was (i) to test the hypothesis that combining Ki67 with residual cancer burden (RCB) following neoadjuvant chemotherapy, as the residual proliferative cancer burden (RPCB), provides significantly more prognostic information than either alone; (ii) to determine whether also integrating information on ER and grade improves prognostic power. PATIENTS AND METHODS: A total of 220 patients treated with neoadjuvant chemotherapy for primary breast cancer were included in the study. Analyses employed a Cox proportional hazard model. Prognostic indices (PIs) were created adding in Ki67, grade and ER to RCB. Leave-one-out cross-validation was used to reduce bias. The overall change in χ(2) of the best model for each index was used to compare the prognostic ability of the different indices. RESULTS: All PIs provided significant prognostic information for patients with residual disease following neoadjuvant chemotherapy. RPCB (χ(2) = 61.4) was significantly more prognostic than either RCB (χ(2) = 38.1) or Ki67 (χ(2) = 53.8) alone P < 0.001. A PI incorporating RCB, Ki67 grade and ER provided the most prognostic information overall and gave χ(2) = 73.8. CONCLUSIONS: This study provides proof of principle that the addition of post-treatment Ki67 to RCB improves the prediction of long-term outcome. Prediction may be further improved by addition of post-treatment grade and ER and warrants further investigation for estimating post-neoadjuvant risk of recurrence. These indices may have utility in stratifying patients for novel therapeutic interventions after neoadjuvant chemotherapy..

PURPOSE: Not all breast cancers respond to lapatinib. A change in Ki67 after short-term exposure may elucidate a biomarker profile for responsive versus nonresponsive tumors. EXPERIMENTAL DESIGN: Women with primary breast cancer were randomized (3:1) to 10 to 14 days of preoperative lapatinib or placebo in a multicenter phase II trial (ISRCTN68509377). Biopsies pre-/posttreatment were analyzed for Ki67, apoptosis, HER2, EGFR, ER, PgR, pAKT, pERK, and stathmin by IHC. Further markers were measured by RT-PCR. Primary endpoint was change in Ki67. HER2(+) was defined as 2+/3+ by IHC and FISH(+). RESULTS: One hundred twenty-one patients (lapatinib, 94; placebo, 27) were randomized; of these, 21% were HER2(+), 78% were HER2(-) nonamplified, 26% were EGFR(+). Paired samples containing tumor were obtained for 98% (118 of 121). Ki67 fell significantly with lapatinib (-31%; P < 0.001), but not with placebo (-3%). Whereas Ki67 reduction with lapatinib was greatest in HER2(+) breast cancer (-46%; P = 0.003), there was a significant Ki67 decrease in HER2(-) breast cancer (-27%; P = 0.017) with 14% of HER2(-) breast cancer demonstrating ≥50% Ki67 reduction with lapatinib. Among HER2(+) patients, the only biomarker predictive of Ki67 response was the EGFR/HER4 ligand epiregulin (EREG) (rho = -0.7; P = 0.002). Among HER2(-) tumors, only HER3 mRNA levels were significantly associated with Ki67 response on multivariate analysis (P = 0.01). In HER2(-) breast cancer, HER2 and HER3 mRNA levels were highly correlated (rho = 0.67, P < 0.001), with all Ki67 responders having elevated HER3 and HER2 expression. CONCLUSIONS: Lapatinib has antiproliferative effects in a subgroup of HER2(-) nonamplified tumors characterized by high HER3 expression. The possible role of high HER2:HER3 heterodimers in predicting response to lapatinib merits investigation in HER2(-) tumors..

BACKGROUND: Chromosomal instability (CIN) has been shown to be associated with drug resistance and poor clinical outcome in several cancer types. However, in oestrogen receptor (ER)-negative breast cancer we have previously demonstrated that extreme CIN is associated with improved clinical outcome, consistent with a negative impact of CIN on tumour fitness and growth. The aim of this current study was to validate this finding using previously defined CIN thresholds in a much larger prospective cohort from a randomised, controlled, clinical trial. PATIENTS AND METHODS: As a surrogate measurement of CIN, dual centromeric fluorescence in situ hybridisation was performed for both chromosomes 2 and 15 on 1173 tumours from the breast cancer TACT trial (CRUK01/001). Each tumour was scored manually and the mean percentage of cells deviating from the modal centromere number was used to define four CIN groups (MCD1-4), where tumours in the MCD4 group were defined as having extreme CIN. RESULTS: In a multivariate analysis of disease-free survival, with a median follow-up of 91 months, increasing CIN was associated with improved outcome in patients with ER-negative cancer (P trend = 0.03). A similar pattern was seen in ER-negative/HER2-negative cancers (Ptrend = 0.007). CONCLUSIONS: This prospective validation cohort study further substantiated the association between extreme CIN and improved outcome in ER-negative breast cancers. Identifying such patients with extreme CIN may help distinguish good from poor prognostic groups, and therefore support treatment and risk stratification in this aggressive breast cancer subtype..

PI3K/AKT/mTOR signaling plays an important role in breast cancer. Its interaction with estrogen receptor (ER) signaling becomes more complex and interdependent with acquired endocrine resistance. Targeting mTOR combined with endocrine therapy has shown clinical utility; however, a negative feedback loop exists downstream of PI3K/AKT/mTOR. Direct blockade of AKT together with endocrine therapy may improve breast cancer treatment. AZD5363, a novel pan-AKT kinase catalytic inhibitor, was examined in a panel of ER(+) breast cancer cell lines (MCF7, HCC1428, T47D, ZR75.1) adapted to long-term estrogen deprivation (LTED) or tamoxifen (TamR). AZD5363 caused a dose-dependent decrease in proliferation in all cell lines tested (GI50 < 500 nmol/L) except HCC1428 and HCC1428-LTED. T47D-LTED and ZR75-LTED were the most sensitive of the lines (GI50 ∼ 100 nmol/L). AZD5363 resensitized TamR cells to tamoxifen and acted synergistically with fulvestrant. AZD5363 decreased p-AKT/mTOR targets leading to a reduction in ERα-mediated transcription in a context-specific manner and concomitant decrease in recruitment of ER and CREB-binding protein (CBP) to estrogen response elements located on the TFF1, PGR, and GREB1 promoters. Furthermore, AZD5363 reduced expression of cell-cycle-regulatory proteins. Global gene expression highlighted ERBB2-ERBB3, ERK5, and IGFI signaling pathways driven by MYC as potential feedback-loops. Combined treatment with AZD5363 and fulvestrant showed synergy in an ER(+) patient-derived xenograft and delayed tumor progression after cessation of therapy. These data support the combination of AZD5363 with fulvestrant as a potential therapy for breast cancer that is sensitive or resistant to E-deprivation or tamoxifen and that activated AKT is a determinant of response, supporting the need for clinical evaluation..

Overcoming primary or secondary endocrine resistance in breast cancer remains critical to further enhancing the benefit of existing therapies such as tamoxifen or an aromatase inhibitor (AI). Much progress has been made in understanding the molecular biology associated with secondary endocrine resistance. Cotargeting the estrogen receptor, together with various key intracellular proliferation and cell survival signaling pathways, has been explored as a strategy either to treat endocrine resistance once it develops in the second-line setting or to enhance first-line endocrine responsiveness by preventing secondary resistance from developing via blockade of specific pathways from the outset. While attempts to improve endocrine therapy by adding growth factor inhibitors have been disappointing, success resulting in new drug approvals has been seen in secondary endocrine resistance by treating patients with the mTOR antagonist everolimus in combination with the AI exemestane and, more recently, in the first-line setting, by the addition of the CDK 4/6 inhibitor palbociclib to the AI letrozole. Numerous other therapeutics are being evaluated in combination with endocrine therapies based on supportive preclinical evidence, including inhibitors of PI3K, Akt, HDAC, Src, IGFR-1, and FGFR. Appropriate clinical trial design and patient selection based on prior therapy exposure, together with predictive biomarkers derived through real-time molecular profiling, are needed to enrich future trials and maximize any additional benefit that cotargeting may bring to current endocrine therapies for estrogen receptor-positive breast cancer..

Breast cancer is the most common cancer in women worldwide. The majority of deaths attributed to breast cancer are a result of metastatic disease, and 30% of early breast cancers (EBC) will develop distant disease. The 5-year survival of patients with metastatic disease is estimated at 23%. Breast cancer subtypes continue to be stratified histologically on oestrogen, progesterone and human epidermal growth factor-2 (HER2) receptor expression. HER2-positive breast cancers represent 25% of all breast cancer diagnoses. The therapies available for metastatic breast cancer (MBC) are expanding, in particular within the field of HER2-positive disease, with the approval of trastuzumab, pertuzumab, lapatinib and trastuzumab emtansine (TDM-1). Recently, TDM-1 has been shown to improve progression-free survival in HER2 MBC when compared to capecitabine and lapatinib in clinical studies. Its main toxicities are deranged liver function tests and thrombocytopenia. There have also been cases of acute liver failure. Therefore, its use in acute hepatic dysfunction, to our knowledge, has been neither studied nor reported. We report a patient with progressive HER2-positive MBC who had previously responded to multiple HER2-targeted therapies that presented with acute hepatic dysfunction. She was treated with dose-reduced TDM-1 safely, with clear evidence of rapid biochemical, clinical and radiological response. This allowed dose escalation of TDM-1, and the patient maintains an ongoing response..

PURPOSE: Lapatinib, a dual epidermal growth factor receptor (EGFR) and HER2 inhibitor, remains unproven in non-HER2-amplified metastatic breast cancer (MBC). EGF30008, a phase III trial of letrozole and lapatinib versus letrozole and placebo, demonstrated that lapatinib significantly improves outcome for postmenopausal women with HER2-amplified, but not HER2-negative, MBC. The hypothesis that low hormone receptor status is associated with benefit in this HER2-negative cohort was tested. EXPERIMENTAL DESIGN: A blinded retrospective biomarker evaluation used immunohistochemistry (IHC) to semiquantify estrogen receptor (ER) and progesterone receptor (PgR) expression (n = 821/952). HER2 status was determined by IHC and confirmed by FISH (n = 326). Effects of these biomarkers on progression-free survival (PFS) were examined in patients with available tissue. RESULTS: In HER2-negative, ER-positive MBC, median PFS was analyzed by ER and PgR expression (H-score) by quartile (Q). There was significant improvement in patients with low ER expression (Q1, H-score <160) with lapatinib and letrozole (13.6 vs. 6.7 months; P = 0.01). No benefit was associated with stronger ER expression (Q2/3, H-score ≥ 160 and <250; 13.6 vs. 14.2 months; Q4, H-score ≥ 250; 11.2 vs. 14.2 months). There was no association between PgR H-score and benefit from lapatinib. CONCLUSION: In postmenopausal patients with advanced hormone receptor-positive disease, weak ER expression is associated with worse outcome with letrozole treatment compared with the combination. The addition of lapatinib significantly improved PFS for this patient subgroup and augments data supporting interaction between steroid hormone and peptide hormone signaling. A prospective study validating this hypothesis is required..

The TACT trial is the largest study assessing the benefit of taxanes as part of adjuvant therapy for early breast cancer. The goal of this translational study was to clarify the predictive and prognostic value of Tau within the TACT trial. Tissue microarrays (TMA) were available from 3,610 patients. ER, PR, HER2 from the TACT trial and Tau protein expression was determined by immunohistochemistry on duplicate TMAs. Two parallel scoring systems were generated for Tau expression ('dichotomised' vs. 'combined' score). The positivity rate of Tau expression was 50 % in the trial population (n = 2,483). Tau expression correlated positively with ER (p < 0.001) and PR status (p < 0.001); but negatively with histological grade (p < 0.001) and HER2 status (p < 0.001). Analyses with either scoring systems for Tau expression demonstrated no significant interaction between Tau expression and efficacy of docetaxel. Contrary to the hypothesis that taxane benefit would be enriched in Tau negative/low patients, the only groups with a suggestion of a reduced event rate in the taxane group were the HER2-positive, Tau positive subgroups. Tau expression was seen to be a prognostic factor on univariate analysis associated with an improved DFS, independent of the treatment group (p < 0.001). It had no prognostic value in ER-negative tumours and the weak prognostic effect of Tau in ER-positive tumours (p = 0.02) diminished, when considering ER as an ordinal variable. On multivariable analyses, Tau had no prognostic value in either group. In addition, no significant interaction between Tau expression and benefit from docetaxel in patients within the PR-positive and negative subsets was seen. This is now the second large adjuvant study, and the first with quantitative analysis of ER and Tau expression, failing to show an association between Tau and taxane benefit with limited utility as a prognostic marker for Tau in ER-positive early breast cancer patients..

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To review the available published data regarding the incidence, mechanisms of pathogenesis, clinical presentations and management of pneumonitis caused by anti-cancer treatments (radiotherapy (RT) and systemic agents) that are included in the guidelines of the treatment of breast cancer (BC) and address the issues on the current grading classification of pneumonitis. A literature search was performed between July and October 2013 using PubMed for papers published from January 1989 to October 2013. Any clinical trial, case report, case series, meta-analysis or systematic review that reported on pulmonary toxicity of any BC therapeutic modality was included (only papers published in English). Most of anticancer treatments currently used in the management of BC may induce some degree of pneumonitis that is estimated to have an incidence of 1-3 %. There is an obvious distinction between chemotherapy- and targeted treatment-related lung toxicity. Moreover, the current classification of pneumonitis needs to be modified as there is a clear diversity in grade 2. As pneumonitis is relatively common and reported as side effect of new anticancer agents, physicians need to be aware of the clinical and radiological manifestations of drug- and RT-induced toxicities in patients with BC. A key recommendation is the subdivision of grade 2 cases to two subgroups. We provide an algorithm, along with real life cases as managed in the breast Unit of Royal Marsden Hospital, with the aim to guide physicians in managing all possible eventualities that may come across in clinical practise..

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AIMS: Low rates of adjuvant chemotherapy use are frequently reported in older women with early breast cancer. One of the reasons for this may be the risk of febrile neutropaenia or the perception that older patients will probably not complete the chemotherapy course prescribed. There are no data regarding these adverse outcomes in routine clinical practice. PATIENTS AND METHODS: We identified 128 patients aged 70 years or over who received neoadjuvant or adjuvant chemotherapy for early breast cancer in seven UK cancer centres between 2006 and 2012. Data were collected regarding standard clinical and pathological variables and treatment toxicity and outcomes. RESULTS: Twenty-four patients (19%) had an episode of febrile neutropaenia. Overall, 27 patients (21%) did not complete their planned therapy. Chemotherapy discontinuation was more common in those patients with an episode of febrile neutropaenia (46% versus 16%, P = 0.004). Thirty patients (23%) were admitted with chemotherapy-related complications. There were no treatment-related deaths. CONCLUSIONS: The rates of febrile neutropaenia and treatment discontinuation are high in women aged 70 years or over receiving adjuvant chemotherapy for breast cancer. Close attention should be paid to the choice or regimen and the use of supportive therapies in this patient population..

Adjuvant endocrine therapy has made a significant impact in improving overall survival for women with hormone receptor (HR)-positive breast cancer. The anti-estrogen tamoxifen is the most widely used therapy, although in post-menopausal women, aromatase inhibitors (AIs) have further improved outcomes either as an alternative to tamoxifen for 5 years, or given in sequential fashion following initial tamoxifen therapy. However, late recurrence remains perhaps the biggest risk in HR-positive breast cancer, with more than half all recurrences occurring beyond 5 years since primary diagnosis. As such, the current debate is whether extended AI or prolonged tamoxifen therapy should be given, and if so, to whom. We review some of the recent studies that have addressed this question and demonstrated further reduction in risk of recurrence, and discuss the clinical issues that face women and their health care providers in determining who should use which drug, and for how long..

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Adjuvant systemic therapies for breast cancer have led to a significant reduction in the risk of relapse and improvement in overall survival. However, a substantial proportion of breast cancer patients still ultimately experience relapse with metastatic disease. Here we review recent progress in trials of systemic therapies, including endocrine therapy, chemotherapy and targeted therapies for breast cancer. A current challenge for translational research is to identify drivers of resistance that may be amenable to therapy, as well as potential compensatory mechanisms that might limit the effectiveness of novel therapies. Unfortunately, not all targeted agents entering clinical trials will show sufficient efficacy to be approved for use. We highlight key findings from trials of novel agents, and the need for further research to identify biomarkers of response to systemic therapies in breast cancer..

This phase II study (VEG20007; NCT00347919) with randomized and open-label components evaluated first-line lapatinib plus pazopanib therapy and/or lapatinib monotherapy in patients with human epidermal growth factor receptor type 2 (HER2)-positive advanced/metastatic breast cancer. Patients were enrolled sequentially into two cohorts: Cohort 1, patients were randomly assigned to lapatinib 1,000 mg plus pazopanib 400 mg or lapatinib 1,500 mg monotherapy; Cohort 2, patients received lapatinib 1,500 mg plus pazopanib 800 mg. The primary endpoint was week-12 progressive disease rate (PDR) for Cohort 1. The principal secondary endpoint was week-12 response rate (RR) for Cohort 2. Efficacy was assessed in patients with centrally confirmed HER2 positivity (modified intent-to-treat population [MITT]). The study enrolled 190 patients (Cohort 1, combination n = 77, lapatinib n = 73; Cohort 2, n = 40). The MITT population comprised n = 141 (Cohort 1) and n = 36 (Cohort 2). In Cohort 1, week-12 PDRs were 36.2 % (combination) versus 38.9 % (lapatinib; P = 0.37 for the difference). Week-12 RRs were 36.2 % (combination) versus 22.2 % (lapatinib). In Cohort 2, week-12 RR was 33.3 %. In Cohort 1, grade 3/4 adverse events (AEs) included diarrhea (combination, 9 %; lapatinib, 5 %) and hypertension (combination, 5 %; lapatinib, 0 %). Grades 3/4 AEs in Cohort 2 included diarrhea (40 %), hypertension (5 %), and fatigue (5 %). Alanine aminotransferase elevations >5 times the upper limit of normal occurred in Cohort 1 (combination, 18 %; lapatinib, 5 %) and Cohort 2 (20 %). Upon conclusion, the combination of lapatinib plus pazopanib did not improve PDR compared with lapatinib monotherapy, although RR was increased. Toxicity was higher with the combination, including increased diarrhea and liver enzyme elevations..

Results from the NSABP B-28 trial suggest AKT activation may predict reduced benefit from taxanes following standard anthracycline therapy. Pre-clinical data support a link between PI3 K/AKT signalling and taxane resistance. Using the UK taxotere as adjuvant chemotherapy trial (TACT), we tested the hypothesis that activation of AKT or downstream markers, p70S6K or p90RSK, identifies patients with reduced benefit from taxane chemotherapy. TACT is a multi-centre open-label phase III trial comparing four cycles of standard FEC (fluorouracil, epirubicin, cyclophosphamide) followed by four cycles of docetaxel versus eight cycles of anthracycline-based chemotherapy. Samples from 3,596 patients were available for the current study. We performed immunohistochemical analysis of activation of AKT, p70S6 K and p90RSK. Using a training set with multiple cut-offs for predictive values (10 % increments in expression), we found no evidence for a treatment by marker interaction for pAKT473, pS6 or p90RSK. pAKT473, pS6 and p90RSK expression levels were weakly correlated. A robust, preplanned statistical analysis in the TACT trial found no evidence that pAKT473, pS6 or p90RSK identifies patients deriving reduced benefit from adjuvant docetaxel. This result is consistent with the recent NASBP B28 study where the pAKT473 effect is not statistically significant for the treatment interaction test. Therefore, neither TACT nor NASBP-B28 provides statistically robust evidence of a treatment by marker interaction between pAKT473 and taxane treatment. Alternative methods for selecting patients benefitting from taxanes should be explored..

Chromosomal instability, which is a characteristic of many human cancers, contributes to intratumour heterogeneity and has been functionally implicated in resistance to taxane therapy in tumour models. However, defining the status of tumour chromosomal instability in a given tumour to test this hypothesis remains challenging. Measurements of numerical and structural chromosomal heterogeneity demonstrate that histological grade correlates with chromosomal instability in oestrogen receptor (ER)-positive breast cancer. Using data on adjuvant taxane therapy in women with breast cancer, we propose that patients with low-grade ER-positive tumours, which are thought to be chromosomally stable, might derive unexpected benefit from taxane therapy. We discuss the implications of the relationships between tumour grade, chromosomal instability and intratumour heterogeneity, the development of high-throughput methods to define tumour chromosomal instability and the potential use of chromosomal instability to tailor therapy..

BACKGROUND: The optimum endocrine treatment for postmenopausal women with advanced hormone-receptor-positive breast cancer that has progressed on non-steroidal aromatase inhibitors (NSAIs) is unclear. The aim of the SoFEA trial was to assess a maximum double endocrine targeting approach with the steroidal anti-oestrogen fulvestrant in combination with continued oestrogen deprivation. METHODS: In a composite, multicentre, phase 3 randomised controlled trial done in the UK and South Korea, postmenopausal women with hormone-receptor-positive breast cancer (oestrogen receptor [ER] positive, progesterone receptor [PR] positive, or both) were eligible if they had relapsed or progressed with locally advanced or metastatic disease on an NSAI (given as adjuvant for at least 12 months or as first-line treatment for at least 6 months). Additionally, patients had to have adequate organ function and a WHO performance status of 0-2. Participants were randomly assigned (1:1:1) to receive fulvestrant (500 mg intramuscular injection on day 1, followed by 250 mg doses on days 15 and 29, and then every 28 days) plus daily oral anastrozole (1 mg); fulvestrant plus anastrozole-matched placebo; or daily oral exemestane (25 mg). Randomisation was done with computer-generated permuted blocks, and stratification was by centre and previous use of an NSAI as adjuvant treatment or for locally advanced or metastatic disease. Participants and investigators were aware of assignment to fulvestrant or exemestane, but not of assignment to anastrozole or placebo. The primary endpoint was progression-free survival (PFS). Analyses were by intention to treat. This trial is registered with ClinicalTrials.gov, numbers NCT00253422 (UK) and NCT00944918 (South Korea). FINDINGS: Between March 26, 2004, and Aug 6, 2010, 723 patients underwent randomisation: 243 were assigned to receive fulvestrant plus anastrozole, 231 to fulvestrant plus placebo, and 249 to exemestane. Median PFS was 4·4 months (95% CI 3·4-5·4) in patients assigned to fulvestrant plus anastrozole, 4·8 months (3·6-5·5) in those assigned to fulvestrant plus placebo, and 3·4 months (3·0-4·6) in those assigned to exemestane. No difference was recorded between the patients assigned to fulvestrant plus anastrozole and fulvestrant plus placebo (hazard ratio 1·00, 95% CI 0·83-1·21; log-rank p=0·98), or between those assigned to fulvestrant plus placebo and exemestane (0·95, 0·79-1·14; log-rank p=0·56). 87 serious adverse events were reported: 36 in patients assigned to fulvestrant plus anastrozole, 22 in those assigned to fulvestrant plus placebo, and 29 in those assigned to exemestane. Grade 3-4 adverse events were rare; the most frequent were arthralgia (three in the group assigned to fulvestrant plus anastrozole; seven in that assigned to fulvestrant plus placebo; eight in that assigned to exemestane), lethargy (three; 11; 11), and nausea or vomiting (five; two; eight). INTERPRETATION: After loss of response to NSAIs in postmenopausal women with hormone-receptor-positive advanced breast cancer, maximum double endocrine treatment with 250 mg fulvestrant combined with oestrogen deprivation is no better than either fulvestrant alone or exemestane..

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Overcoming de novo or acquired endocrine resistance remains critical to further enhancing the benefit of existing endocrine therapies. Recent progress has been made in understanding the molecular biology associated with acquired endocrine resistance, including adaptive "cross-talk" between ER and various growth factor receptor and cell-signaling pathways. Strategies that combine endocrine therapy with targeted inhibitors of growth factor receptors or cell-survival pathways to further enhance first-line response have largely been disappointing, suggesting that any attempts to prevent endocrine resistance by blocking specific pathways from the outset will be futile. In contrast, success has been seen by selecting patients with acquired endocrine resistance and enhancing response to further endocrine therapy by the addition of mTOR antagonists. Numerous other therapeutics are being evaluated in combination with endocrine therapies based on varying levels of preclinical science to support their use, including inhibitors of PI3K, HDAC, Src, IGFR-1, and CDK4/6. Enriching trial recruitment by molecular profiling of different ER+ subtypes will become increasingly important to maximize any additional benefit that these new agents may bring to current endocrine therapies for breast cancer..

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Over the past 120 years, the discipline of oncology has evolved so that a multitude of anatomical and increasingly complex functional imaging techniques are now applicable in both clinical and research platforms. This Timeline article revisits the achievements of the pioneer techniques in cancer imaging, discusses how these techniques have changed over time, provides some examples of clinical importance, and ventures to explain how imaging will remodel the future of modern oncology..

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INTRODUCTION: Strategies to improve the efficacy of endocrine agents in breast cancer (BC) therapy and to delay the onset of resistance include concomitant targeting of the estrogen receptor alpha (ER) and the mammalian target of rapamycin complex 1 (mTORC1), which regulate cell-cycle progression and are supported by recent clinical results. METHODS: BC cell lines expressing aromatase (AROM) and modeling endocrine-sensitive (MCF7-AROM1) and human epidermal growth factor receptor 2 (HER2)-dependent de novo resistant disease (BT474-AROM3) and long-term estrogen-deprived (LTED) MCF7 cells that had acquired resistance associated with HER2 overexpression were treated in vitro and as subcutaneous xenografts with everolimus (RAD001-mTORC1 inhibitor), in combination with tamoxifen or letrozole. End points included proliferation, cell-cycle arrest, cell signaling, and effects on ER-mediated transactivation. RESULTS: Everolimus caused a concentration-dependent decrease in proliferation in all cell lines, which was associated with reductions in S6 phosphorylation. Everolimus plus letrozole or tamoxifen enhanced the antiproliferative effect and G1-accumulation compared with monotherapy, as well as increased phosphorylation (Ser10) and nuclear accumulation of p27 and pronounced dephosphorylation of Rb. Sensitivity was greatest to everolimus in the LTED cells but was reduced by added estrogen. Increased pAKT occurred in all circumstances with everolimus and, in the BT474 and LTED cells, was associated with increased pHER3. Decreased ER transactivation suggested that the effectiveness of everolimus might be partly related to interrupting cross-talk between growth-factor signaling and ER. In MCF7-AROM1 xenografts, letrozole plus everolimus showed a trend toward enhanced tumor regression, versus the single agents. In BT474-AROM3 xenografts, everolimus alone was equally effective at reducing tumor volume as were the combination therapies. CONCLUSIONS: The results provide mechanistic support for recent positive clinical data on the combination of everolimus and endocrine therapy, as well as data on potential routes of escape via enhanced HER2/3 signaling. This merits investigation for further improvements in treatment efficacy..

The benefit of endocrine therapy has always been limited by the eventual development of acquired resistance. For the first time, clinical research has identified a therapeutic agent, everolimus, that targets the mammalian target of rapamycin (mTOR), which in combination with the aromatase inhibitor exemestane can substantially reduce the risk of disease progression and seemingly circumvent endocrine resistance. The magnitude of the benefit represents a quantum shift in how we should use endocrine therapy in future, and potentially defines a new standard of care in this setting..

Adjuvant endocrine therapy for early-stage breast cancer has had the single biggest impact on improving survival from the disease-with tamoxifen alone contributing to saving many thousands of lives. In postmenopausal women, additional progress has been made by the incorporation of aromatase inhibitors into the treatment of early-stage, estrogen receptor (ER)-positive breast cancer, as several large well-conducted trials have established either "up-front" or "switch" strategies that are now widely used. To date, both have been shown to be beneficial when compared with tamoxifen alone, although controversy exists as to which approach is superior. Increasingly, extended adjuvant therapy is being considered, as "longer may be better" for some women who have an ongoing risk of recurrence beyond 5 years. However, controversy remains as to how long adjuvant endocrine therapy should be given for; in clinical practice, clinicians balance the level of risk for individual patients versus any ongoing toxicity concerns. For premenopausal women, with ER-positive breast cancer, tamoxifen remains the gold standard with uncertainty in the added overall benefit of ovarian suppression. Important clinical trials have recently been completed that may help answers this question, including whether complete estrogen deprivation using a luteinizing hormone releasing hormone (LHRH) agonist plus aromatase inhibitors (AIs) is of added benefit. In recent years, molecular profiling of ER-positive breast cancer has started to distinguish those women with a low risk of recurrence on endocrine therapy who may not need chemotherapy. Thus, with more therapy options and greater tumour stratification, modern, adjuvant endocrine therapy is becoming increasingly personalised to suit each individual patient's risk..

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Aromatase inhibitors (AI) have improved the treatment of oestrogen receptor positive (ER+) breast cancer. Despite the efficacy of these agents over 40% of patients relapse with endocrine resistant disease. Here we describe an in vitro model of acquired resistance to long-term oestrogen deprivation (LTED). The LTED cells retain expression of the ER and appear hypersensitive to oestrogen as a result of altered kinase activity. Furthermore analysis of temporal changes in gene expression during the acquisition of resistance highlight growth factor receptor pathways as key mediators of this adaptive process..

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Metastatic breast cancer has always been a challenging disease to treat, with cytotoxic chemotherapy often being deemed a merely palliative treatment that is given to relieve cancer-related symptoms. However with the introduction of more effective systemic therapies over the last two decades, recently we have witnessed substantial improvements in clinical outcomes such that many patients now live with metastatic secondary breast cancer for many years. Various different cytotoxics are used in clinical practice, and targeted biological therapeutics have an increasing role to play in the management of different breast cancer subtypes. The appropriate use of these different systemic therapeutics has been one of the principal reasons for the continued improvement in clinical outcomes for women with advanced breast cancer, including a probable substantial impact on overall survival..

Development of resistance to the antioestrogen tamoxifen occurs in a large proportion of patients with oestrogen receptor-positive (ER+) breast cancer and is an important clinical challenge. While loss of ER occurs in c.20% of tamoxifen-resistant tumours, this cannot be the sole explanation for tamoxifen treatment failure. PI3K pathway activation, including by insulin-like growth factor receptor 1 (IGF1R), has been implicated in some resistance models. The primary aim was to determine whether evidence exists in clinical breast cancer for a role of IGF1R and/or the PI3K pathway, in acquisition of resistance to tamoxifen. Invasive primary and recurrent tamoxifen-resistant tumours from the same patient (n=77) were assessed for changes in ER, progesterone receptor (PgR), human epidermal growth factor receptor 2 (HER2), IGF1R, stathmin, PTEN expression and PIK3CA mutations where possible. ER and PgR levels were significantly reduced at recurrence with 22 and 45%, respectively, showing negative status at this time. Acquisition of HER2 overexpression occurred in 6% of cases. IGF1R expression was significantly reduced in both ER+ and ER- recurrences and stathmin levels increased. A positive association between stathmin and IGF1R emerged in recurrent samples, despite their opposing relationships with ER, suggesting some coalescence of their activities may be acquired. The data confirm loss of ER and PgR and gain of HER2 in some tamoxifen-resistant tumours. There is no evidence for IGF1R gain in tamoxifen resistance; increases in stathmin levels suggest that activation of the PI3K pathway may have contributed, but PTEN loss and PIK3CA hotspot mutations were relatively rare..

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2525 Background: Many advanced ER+ breast cancer pts show intrinsic resistance to endocrine treatment with the remainder acquiring resistance. Androgenic steroids upstream of aromatase can drive steroid receptor signaling critical to tumour growth. Evidence also exists for an ERα-/AR+ subset of breast cancers transcriptionally similar to ERα+ disease. We hypothesized that AA, a cytochrome (CYP) 17 inhibitor that irreversibly inhibits androgen and estrogen synthesis, would have anti-tumour activity in ER+ or ER-/AR+ pts. METHODS: Post-menopausal women with ER+ or ER-/AR+ advanced breast cancer resistant to >2 lines of hormone therapies were treated in 6-pt cohorts with AA at doses between 250 and 2000mg daily. RESULTS: A total of 25 pts were treated in the phase I trial with 2 pts ongoing on study. Median time on treatment was 1.8 mths (range 0.7 - 11.6 mths). There were no dose limiting toxicities. The majority of adverse events (AEs) were Common Toxicity Criteria grade 1 or 2: fatigue, nausea, anorexia, dyspnoea, palpitations, dizziness and flushes. Hypokalemia was frequent, due to secondary mineralocorticoid syndrome: grade 3/4 hypokalemia occurred in 4 pts. This was effectively managed with potassium supplementation, hydrocortisone (20 mg mane, 10 mg nocte) and eplerenone (50-200 mg) with no clinical consequences. Other grade 3 AEs were neutropenia and reduced left ventricular ejection fraction (1 pt) and exercise-induced hypotension with dizziness (1 pt). At the 2000mg dose 5/5 subjects had suppression of estradiol, testosterone, DHEA and DHEAS to below the lower limit of detection of the assay. Two pts (both ER+/AR+) continued on study beyond 11 mths, one of whom achieved a radiological partial response and 80% reduction in serum CA15.3 from baseline. Pharmacokinetic data will be presented. CONCLUSIONS: AA is well tolerated in advanced breast cancer pts with preliminary evidence of antitumour activity. The predominant AEs are mechanism-based (hypokalemia) and can be managed expectantly, although careful monitoring of potassium levels is recommended..

TPS105 Background: HER2 gene product is overexpressed in ~20% of breast cancer and is associated with an aggressive phenotype and poor prognosis. Finding suitable patients with HER2+ MBC who adhere to strict protocol criteria, coupled with various competitive clinical trials presents recruitment challenges. A 3-trial approach that enrolls patients in different HER2+ MBC settings with nonoverlapping inclusion criteria may boost recruitment at each center. METHODS: Three ongoing global phase III trials are examining the clinical profile of lapatinib (Table). COMPLETE (EGF108919; NCT00667251 ) is a study of taxane-based chemotherapy with lapatinib or trastuzumab, followed by lapatinib or trastuzumab monotherapy, as first-line therapy for HER2+ MBC patients. The primary endpoint is progression-free survival (PFS); secondary endpoints include overall survival (OS), time to CNS metastases at first progression, and incidence of CNS metastases at progression. EGF114299 ( NCT01160211 ) tests an aromatase inhibitor (AI) in combination with lapatinib, trastuzumab, or both in HR+, HER2+ postmenopausal MBC patients. The primary endpoint compares OS in the lapatinib/trastuzumab/AI arm vs trastuzumab/AI arm. Secondary endpoints include OS in the lapatinib/AI vs trastuzumab/AI arms and lapatinib/trastuzumab/AI vs lapatinib/AI arms, PFS, and biomarker evaluation. CEREBEL (EGF111438; NCT00820222 ) examines the incidence of CNS metastasis as site of first relapse on lapatinib+capecitabine vs trastuzumab+capecitabine in HER2+ MBC patients previously treated with anthracyclines or taxanes and with an independently reviewed baseline MRI scan confirming no CNS metastases. Secondary endpoints include PFS, time to first CNS metastasis, and OS. Each study is open to accrual and will further elucidate the role of lapatinib in multiple settings of HER2+ MBC. [Table: see text]..

BACKGROUND: Recent UK clinical guidance advises against continuing trastuzumab (T) beyond disease progression (PD) in the absence of brain metastases in patients with HER-2 positive (+ve) advanced breast cancer .We have retrospectively evaluated the outcome of patients with HER-2+ve locally advanced (LA) or metastatic breast cancer (MBC) who continued T beyond PD, treated in our unit. METHODS: All HER-2+ve patients on our prospectively maintained database with LA or MBC who received T beyond PD after adjuvant or one line of T for advanced disease were assessed for response and outcome. From the timepoint of T continuation beyond PD, we calculated the overall disease control rate, time to progression (TTP), and overall survival (OS). RESULTS: One hundred and fourteen patients with HER-2+ve LA or MBC treated with T beyond PD were identified. The main site of disease was visceral in 84 (74%) patients. Seventy-six (66%) had one line of chemotherapy before continuation of T beyond PD and 21 (19%) had two or more. Post-progression, 66 (58%) received T combined with chemotherapy. Of the 93 (82%) patients with documented clinical or radiological response evaluation, 67 (59%) were considered as having stable disease or better. The median TTP was 24 weeks (95% CI: 21-28) and the median OS was 19 months (95% CI: 12-24). CONCLUSION: Our results from an unselected group of patients provide additional evidence that continuation of T beyond PD is of clinical benefit..

PURPOSE: Acquired endocrine resistance in estrogen receptor (ER)alpha+/human epidermal growth factor receptor 2-negative (HER2-) breast cancer has been associated with modest adaptive increases in HER2, although exactly how aberrant HER2 signaling affects the ERalpha pathway is poorly understood. We investigated (a) whether the epidermal growth factor receptor/HER2 inhibitor lapatinib could restore endocrine responsiveness in cell models of acquired endocrine resistance with modest increases in HER2, and (b) the nature of ERalpha-HER2 cross-talk in this process. METHODS: Combination growth studies, ERalpha transcription, immunoblot, and gene expression assays were conducted in two models of acquired resistance to (a) estrogen deprivation (long-term estrogen-deprived cells) and (b) tamoxifen (long-term tamoxifen-treated cells), and in hormone sensitive controls. Changes in ERalpha, PgR, and HER2 were assessed in samples from patients treated with tamoxifen. RESULTS: Both cell models of acquired endocrine resistance showed modest adaptive upregulation in HER2, and lapatinib restored endocrine sensitivity in both. The effect of lapatinib on ERalpha signaling varied markedly depending on the nature of the HER2/ERalpha cross-talk. In long-term estrogen-deprived cells characterized by enhanced ERalpha function, lapatinib suppressed ERalpha genomic activity (as measured by pERSer118, ERalpha transcriptional activity, and PGR gene expression). In contrast, in long-term tamoxifen-treated cells with reduced ERalpha activation, lapatinib reactivated ERalpha genomic function. Twenty percent of tamoxifen-resistant patients relapsed with modest increases in HER2 and either suppressed or enhanced ERalpha/PgR expression. CONCLUSIONS: Aberrant GFR signaling can augment or suppress ERalpha function. Regardless, interrupting the HER2/ERalpha cross-talk with lapatinib can restore endocrine sensitivity and should be investigated as a therapeutic strategy in combination with endocrine therapy in ERalpha+/HER2- patients with acquired endocrine resistance..

Chromosomal instability (CIN) is a common cause of tumour heterogeneity and poor prognosis in solid tumours and describes cell-cell variation in chromosome structure or number across a tumour population. In this article we consider evidence suggesting that CIN may be targeted and may influence response to distinct chemotherapy regimens, using HER2-positive breast cancer as an example. Pre-clinical models have indicated a role for HER2 signalling in initiating CIN and defective cell-cycle control, and evidence suggests that HER2-targeting may attenuate this process. Anthracyclines and platinum agents may target tumours with distinct patterns of karyotypic complexity, whereas taxanes may have preferential activity in tumours with relative chromosomal stability. A greater understanding of karyotypic complexity and identification of methods to directly examine and target CIN may support novel strategies to improve outcome in cancer..

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BACKGROUND: Treatments for inflammatory breast cancer (IBC) have changed over the last 15 to 20 years. The authors of this report undertook a retrospective review of patients who were treated at the Royal Marsden Hospital (RMH) to determine whether recurrence-free survival (RFS) and overall survival (OS) have improved as treatment regimens have altered. METHODS: Detailed clinical-pathologic data were collected on patients who were treated for primary IBC at RMH between 1990 and 2007. A Cox regression model was used to investigate the factors that influenced OS. RESULTS: The median OS was 3 years and 4 months, and the median RFS was 1 year and 10 months. RFS was better in patients who had received taxane-containing regimens; however, there was no OS benefit. A pathologic complete response (pCR) was observed in 13 of 89 patients (15%), and those who achieved a pCR had significantly better RFS but no improvement in OS. The type of chemotherapy did not affect the pCR rate. One hundred thirty of 155 patients received radiotherapy, and those who did not receive radiotherapy had significantly worse outcomes. A multivariate Cox regression analysis indicated that the date of diagnosis, estrogen receptor (ER) status, and the presence of metastatic disease at diagnosis were significant prognostic factors. Patients who were diagnosed during or after 2000 had a relative risk of mortality of 0.5 compared with patients who were diagnosed before 2000. ER-positive patients had a median OS of 4.5 years and a median of RFS of 2.6 years versus 2.9 years and 1.4 years, respectively, for ER-negative patients. Patients who had metastatic disease at presentation had an OS of 1.7 years versus 3.9 years for those without metastatic disease at presentation. CONCLUSIONS: Achieving a pCR improved RFS but had no impact on OS. Patients who had metastatic disease at the outset fared much worse, and positive ER status conferred a better outlook..

Endocrine therapy has led to a significant improvement in outcomes for women with estrogen receptor-positive (ER+) breast cancer. Current questions in the adjuvant setting include the optimal duration of endocrine therapy, and the accurate molecular prediction of endocrine responsiveness using gene array-based assays compared with ER expression itself. In advanced disease, novel selective estrogen receptor antagonists (SERM) have failed to make an impact, although the pure ER antagonist fulvestrant may have a role, albeit optimal dose and sequence remain unclear. Overcoming de novo or acquired endocrine resistance remains critical to enhancing further the benefit of existing endocrine therapies. Recent progress has been made in understanding the molecular biology associated with acquired endocrine resistance, including adaptive "cross-talk" between ER and peptide growth factor receptor pathways such as epidermal growth factor receptor (EGFR)/human epidermal growth factor receptor 2 (HER2). Future strategies that are being evaluated include combining endocrine therapy with inhibitors of growth factor receptors or downstream signaling pathways, to treat or prevent critical resistance pathways that become operative in ER+ tumors. Preclinical experiments have provided great promise for this approach, although clinical data remain mixed. Enriching trial recruitment by molecular profiling of different ER+ subtypes will become increasingly important to maximize additional benefit that new agents may bring to current endocrine therapies for breast cancer..

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Single agent capecitabine is effective and well tolerated in metastatic breast cancer (MBC). We have retrospectively analysed capecitabine outcome as 1st, 2nd or 3rd line chemotherapy in 89 elderly patients ≥70 years with locally advanced or MBC treated in our Unit, 55 (62%) as 1st line and 34 (38%) as 2nd or 3rd line. Starting dose was 1000 mg/m(2) twice daily, days 1-14 every 3 weeks, but 36 (41%) started on a 25% dose reduction because of frailty and 12 (13%) reduced dose after the 1st or the 2nd cycle. Overall response rate (ORR) was 45% (95% CI: 35-55%). A further 19 (21%) achieved stable disease (SD) for ≥6 months. Median time to progression (TTP) and overall survival (OS) were 30 (95% CI: 23-37) and 61 (95% CI: 44-77) weeks, respectively. The ORR for 1st line treatment was 51% compared with 35% for 2nd and 3rd line treatment (p = 0.03). No significant difference in efficacy was seen between patients receiving the full versus reduced dose. Capecitabine was well tolerated, although 35% had treatment delays and 57% required dose reduction. Grade 3-4 toxicities were hand-foot syndrome in 11%, lethargy 9% and diarrhoea 2%. Capecitabine is an effective and well-tolerated drug in elderly patients with MBC including for 1st line treatment. Dose reduction is frequently required but does not appear to affect outcome..

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BACKGROUND: Cross-talk between receptor tyrosine kinases and the oestrogen receptor (ER) is implicated in resistance to endocrine therapy. We investigated whether AEE788 (a combined inhibitor of EGFR, HER2 and VEGFR) plus tamoxifen or letrozole enhanced the individual anti-tumour effects of these agents. METHODS: Breast cancer cell lines modelling endocrine-resistant and -sensitive disease were engineered to express aromatase (A) and examined using proliferation, western blotting and ER-alpha transcription assays. RESULTS: AEE788 enhanced the anti-proliferative effect of tamoxifen and letrozole in ER(+) cell lines (MCF-7 2A, ZR75.1 A3 and BT474 A3). This associated with an elevated G1 arrest and nuclear accumulation of p27. It is noteworthy that AEE788 alone or in combination with endocrine therapy increased the expression of progesterone receptor (PGR) and TFF1 in BT474 A3 cells. This may indicate a mechanism of resistance to AEE788 in ER(+)/HER2(+) breast cancers. In a ZR75.1 A3 xenograft, AEE788 alone or in combination with tamoxifen provided no further benefit compared with letrozole. However, letrozole plus AEE788 produced a significantly greater inhibition of tumour growth compared with letrozole alone. CONCLUSION: These data suggest that AEE788 plus letrozole in breast cancer overexpressing HER2 may provide superior anti-tumour activity, compared with single agents..

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BACKGROUND: The global lapatinib expanded access programme provided access to lapatinib combined with capecitabine for women with HER2-positive metastatic breast cancer (MBC) who previously received anthracycline, taxane and trastuzumab. METHODS: Progression-free survival (PFS) and safety data for 356 patients recruited from the United Kingdom are reported. Efficacy was assessed in 162 patients from the five lead centres, including objective tumour response rate (ORR), time to disease progression (TTP) and efficacy in those with central nervous system (CNS) metastases. Correlation of PFS and ORR with previous capecitabine treatment was also documented. RESULTS: Overall, PFS for the 356 UK patients was 21 weeks (95% CI: 17.6-24.7). In the 162 assessable patients, ORR was 21% (95% CI: 15-27%) and median TTP was 22 weeks (95% CI: 17-27). Efficacy was greater in capecitabine-naive patients (ORR 23 vs 16.3%, P=0.008). For 34 patients with CNS metastases, ORR was 21% (95% CI: 9-39%), with evidence of improvement in neurological symptoms, and median TTP was 22 weeks (95% CI: 15-28). CONCLUSIONS: Lapatinib combined with capecitabine is an active treatment option for women with refractory HER2-positive MBC, including those with progressive CNS disease..

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BACKGROUND AND METHODS: Novel approaches to treat chemo-refractory metastatic breast cancer (MBC) are currently under investigation. This retrospective series reviews the outcome of 70 MBC patients who have participated in 30 phase I trials at the Royal Marsden Hospital from 2002 to 2009. RESULTS: The median treatment lines before phase I trial entry for MBC was 5 (range: 1-12 lines). The overall response rate was 11.4% (95% CI: 4.0-18.9%) and the clinical benefit rate at 4 months was 20% (95% CI: 10.6-29.3). The median time to progression was 7.0 weeks (95% CI: 6.4-7.5) and median overall survival was 8.7 months (95% CI: 7.6-9.8) from start of first phase I treatment. No patients discontinued trial because of treatment-related toxicities. Abnormal lactate dehydrogenase, serum albumin <35 mg per 100 ml, >or=5 previous treatment lines, liver metastases and Eastern Cooperative Group performance status >or=2 at study entry were significantly associated with poor overall survival in multivariate analysis. CONCLUSION: This retrospective analysis provides evidence that patients with MBC tolerate phase I clinical trials and a significant proportion of patients with chemo-refractory disease, particularly those with triple-negative or Her2-positive breast cancer, may benefit from treatment..

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Several selected targeted agents are being investigated in combination with endocrine therapy for patients with breast cancer in an attempt to overcome or prevent endocrine resistance. The role of type I growth factor receptors epidermal growth factor receptor (EGFR) and HER2 in cross-talk with estrogen receptor (ER) signaling has been confirmed in preclinical studies in which various inhibitors have yielded additive or synergistic effects when combined with endocrine agents. Recently, several results from clinical trials investigating this concept have been reported. In ER-positive/HER-positive advanced breast cancer, the addition of trastuzumab to the aromatase inhibitor anastrozole, or the tyrosine kinase inhibitor (TKI) lapatinib to letrozole, both have significantly improved progression-free survival (PFS). The EGFR TKI gefitinib combined with tamoxifen as first-line therapy for ER-positive metastatic disease improved PFS (but not objective response rate) for patients with no previous endocrine therapy or completion of previous adjuvant therapy. A second study in a similar setting showed significant improvement in PFS for gefitinib plus anastrozole. Although it is encouraging that this approach could delay resistance, only a small proportion of patients benefit. Attempts to identify likely responders have been made in the neoadjuvant setting, with pre- and post-treatment biopsies being used to study biomarker changes. A recent preoperative study of letrozole with or without the mammalian target of rapamycin (mTOR) inhibitor everolimus reported greater tumor shrinkage for the combination, with changes in proliferation being predictive for response together with strong expression of protein S6 kinase, a downstream marker of activated mTOR. Key aspects that need to be addressed in future trials include understanding the mechanisms of action for each novel agent, designing the best trial and endpoints to demonstrate added benefit, and ensuring appropriately stratified populations based on previous endocrine exposure and/or sensitivity..

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BACKGROUND: Incorporation of a taxane as adjuvant treatment for early breast cancer offers potential for further improvement of anthracycline-based treatment. The UK TACT study (CRUK01/001) investigated whether sequential docetaxel after anthracycline chemotherapy would improve patient outcome compared with standard chemotherapy of similar duration. METHODS: In this multicentre, open-label, phase III, randomised controlled trial, 4162 women (aged >18 years) with node-positive or high-risk node-negative operable early breast cancer were randomly assigned by computer-generated permuted block randomisation to receive FEC (fluorouracil 600 mg/m(2), epirubicin 60 mg/m(2), cyclophosphamide 600 mg/m(2) at 3-weekly intervals) for four cycles followed by docetaxel (100 mg/m(2) at 3-weekly intervals) for four cycles (n=2073) or control (n=2089). For the control regimen, centres chose either FEC for eight cycles (n=1265) or epirubicin (100 mg/m(2) at 3-weekly intervals) for four cycles followed by CMF (cyclophosphamide 600 mg/m(2), methotrexate 40 mg/m(2), and fluorouracil 600 mg/m(2) at 4-weekly intervals) for four cycles (n=824). The primary endpoint was disease-free survival. Analysis was by intention to treat (ITT). This study is registered as an International Standard Randomised Controlled Trial, number ISRCTN79718493. FINDINGS: All randomised patients were included in the ITT population. With a median follow-up of 62 months, disease-free survival events were seen in 517 of 2073 patients in the experimental group compared with 539 of 2089 controls (hazard ratio [HR] 0.95, 95% CI 0.85-1.08; p=0.44). 75.6% (95% CI 73.7-77.5) of patients in the experimental group and 74.3% (72.3-76.2) of controls were alive and disease-free at 5 years. The proportion of patients who reported any acute grade 3 or 4 adverse event was significantly greater in the experimental group than in the control group (p<0.0001); the most frequent events were neutropenia (937 events vs 797 events), leucopenia (507 vs 362), and lethargy (456 vs 272). INTERPRETATION: This study did not show any overall gain from the addition of docetaxel to standard anthracycline chemotherapy. Exploration of predictive biomarker-defined subgroups might have the potential to better target the use of taxane-based therapy. FUNDING: Cancer Research UK (CRUK 01/001), Sanofi-Aventis, Pfizer, and Roche..

1095 Background: Cardiotoxicity of traztuzumab therapy increases in pts pretreated with anthracyclines (A), radiotherapy to left breast, hypertension, or low baseline ejection fraction (EF). We report the cardiac safety profile of lapatinib, an oral, dual EGFR/HER-2 tyrosine kinase inhibitor, in a chemotherapy naïve or A-exposed pts with MBC. METHODS: Women (n = 1286) with endocrine sensitive, previously untreated MBC received lapatinib and letrozole (L+L) or letrozole and placebo (L+P): 33% received previous A; 48% previous tamoxifen; <1% previous trastuzumab (T); <2% previous aromatase inhibitor. EF was evaluated by MUGA or echocardiogram at baseline, every 8 wk and at study withdrawal. Rate of cardiac events (NCI CTCAE grading), median time to onset, and duration of EF depression were assessed. RESULTS: Cardiac events (CE; MEDRA terms: ejection fraction decreased, left ventricular dysfunction, ventricular dysfunction and cardiac failure) were infrequent in both arms. Grade 3/4 and 1/2 CE were reported in 0.9% and 4.0% of pts, respectively, in the L+L arm, and in 0.3% and 2.1%, respectively, in the L+P arm. The only symptomatic CE was a grade 4 event in the L+L arm. There was no apparent relationship between previous A exposure and CE frequency and severity. Median L exposure was 40 wk on L+L, 38 wk on L+P. Median time to onset and duration of EF decrease were 21.8 and 8.1 wk, respectively, on L+L, and 34.6 and 5.4 wk, respectively on L+ P. On the L+L arm, the dose was adjusted/interupted for 8 CE cases, discontinued for 6, and unchanged for 22. On the L+P arm, interuption of L was reported for 2 CE cases, discontinuation for 5, and in 7 CE events there was no change in therapy. Eight CE on L+L and 1 CE on L+P had not resolved as of the last report. CONCLUSIONS: This is the first long-term evaluation of lapatinib cardiac signals in a controlled trial in a trastuzumab-naïve MBC pt population. The frequency of cardiac events and degree of absolute EF decrease was low and occurred at similar rates in pts with or without anthracycline exposure. These encouraging cardiac safety data in first line metastatic BC study are promising for the ongoing study of lapatinib in patients with early HER-2+ BC treated on ALTTO trial. [Table: see text]..

1039 Background: A phase III randomized double-blind multicenter trial compared lapatinib plus letrozole (L+Let) with letrozole plus placebo (Let), as first-line therapy for hormone receptor positive (HR+) MBC. Median PFS, the primary endpoint of the study, in patients who were HER2+ was significantly prolonged for L+Let compared with Let (8.2 vs 3 months, Hazard Ratio (95% CI)=0.71(0.53,0.96), p=0.019). This analysis focuses on the impact of treatments on QOL in the HER2+ subgroup. METHODS: QOL outcomes included the Functional Assessment of Cancer Therapy-Breast (FACT-B) total, FACT-general (FACT-G), and trial outcome index (TOI) scores assessed at screening, every 12 weeks and at withdrawal. Higher scores indicate better QOL. Changes from baseline were analyzed using analysis of covariance. In a responder analysis, patients achieving minimally important differences in QOL scores (QOL responders) were compared with Fisher's exact test. RESULTS: Among 1,286 patients, 219 were identified as HER2+ (L+Let n=111; Let n=108). Baseline QOL scores were comparable in the two arms. In this population, mean changes in subscale and total QOL scores were generally stable over time in both treatment arms for patients who stayed on study. For example, on the FACT-B, the average change from baseline in both groups was positive at all scheduled visits through Week 48 and the maximum difference between arms was 2.6 points (CI: -5.8, 11). There were no significant differences between the two treatment arms in percentage of QOL responders (Table). CONCLUSIONS: The addition of lapatinib to letrozole significantly increases PFS while maintaining QOL when compared with letrozole alone thus confirming the clinical benefit of the combination therapy in the HR+, HER2+ MBC patient population. This combination provides an effective option in this patient population by maintaining QOL and delaying the need for chemotherapy and its accompanying side effects. [Table: see text] [Table: see text]..

1062 Background: This double-blind, placebo-controlled, phase III trial assessed the benefit of adding lapatinib, an oral EGFR/HER2 tyrosine-kinase inhibitor, to letrozole alone in patients (pts) with HR+ MBC. The previously reported primary endpoint, investigator (INV) assessed PFS in HER2+ tumors, showed a significant benefit from dual therapy. Median PFS in the HR+ HER2+ population increased from 3 months (mo) in the letrozole/placebo group to 8.2 mo in the letrozole/lapatinib group [Hazard Ratio (95% CI)=0.71 (0.53,0.96), stratified log rank p = 0.019]. The HER-2-ve population did not derive benefit from the combination. Benefit from combined treatment was evaluated in a number of pre-planned exploratory subsets, including a noted trend in the HER2-ve population who progressed within 6 mo of receiving prior tamoxifen. METHODS: 1286 pts were randomized to letrozole/lapatinib or letrozole/placebo. HER2 positivity was defined by a positive FISH ratio or by immunohistochemistry (IHC) 3+ in a central laboratory. INV assessed PFS in the sub-populations were analyzed using Kaplan-Meier with stratified log rank to compare treatment arms. These included tumor samples that were FISH borderline1.8-2.2 (n = 52), IHC 2+ (n = 215), HER2 status UNK (n = 115), and neo/adjuvant TN (n = 656). RESULTS: INV assessed PFS demonstrated no significant prolongation for dual therapy for any of the exploratory populations [Hazard Ratio: (95%CI), p-value]; FISH 1.8-2.2 [1.03 (0.55, 1.95), p = 0.918]; IHC 2+ [1.13 (0.82, 1.57), p = 0.441]; HER2 UNK [0.71 (0.45,1.11), p = 0.126]; TN [0.88 (0.73, 1.07), [p = 0.199]. CONCLUSIONS: The combination of letrozole and lapatinib did not significantly improve PFS in any of the pts with lower levels of HER2 expression (borderline FISH, IHC 2+, or HER2 UNK) or in TN pts. These data confirm the HER2-ve result previously reported and substantiate that only tumors with the target benefit from the addition of a targeted therapy. [Table: see text]..

1019 Background: Elevated baseline sECD (BsECD) correlates weakly with HER2 overexpression (HER2+). HR+ MBC. Lapatinib benefit was reported in pts with HER2+ tumors irrespective of BsECD status; BsECD status did not predict benefit for HER2- negative (HER2-ve) tumors. sECD levels and their predictive and prognostic value for progression-free survival (PFS) were further examined in a randomized, phase III trial of letrozole ± lapatinib. METHODS: Pts (n=1286) with HR+ MBC were randomized to letrozole with placebo (P) or lapatinib (L). HER2 status was evaluated by FISH or IHC in archived tissue. sECD was measured by ELISA at baseline (n=1102 available samples), and every 4 wk. Pts were considered sECD+ if serum sECD was >15 ng/ml. RESULTS: BsECD was positive in 14% (125/894) and 42% (87/208) of pts with HER2-ve and HER2+ tumors, respectively. Correlation between BsECD and FISH was weak but significant in HER2+ pts (R=0.35, p<0.0001) but not in HER2-ve pts (R=0.03, p=0.362). Unlike for HER2+ tumors, BsECD+ did not predict benefit in PFS from L in pts with HER2-ve tumors. HR: Hazard Ratio In pts with HER2- ve tumors, median ECD levels were stable in the P arm but increased slightly (4 ng/mL) in the L arm. In the HER2+ group, median levels in the P arm declined (3.5 ng/mL) but increased at 4 wk in L arm (3.4 ng/mL) and were stable thereafter. Conversion from sECD-ve to sECD+ was observed in both arms but did not correlate with outcome or provide predictive value. Data related to ECD status conversion will be reported. CONCLUSIONS: BsECD+ status correlates with HER2+ tumor status and may predict L benefit but BsECD+ status did not predict benefit in pts with HER2-ve tumors. On therapy changes in median sECD were small. Conversion from BsECD-ve to sECD+ did not predict L benefit and we could not confirm that evaluation of on treatment ECD status may help treatment decision. [Table: see text] [Table: see text]..

1018 Background: Lapatinib (Lap), an oral, dual inhibitor of EGFR/HER-2, is approved with capecitabine for treatment of HER-2+ MBC for recurrence after taxane, anthracycline, and trastuzumab-based therapy. Letrozole (Let) has activity in hormone-receptor positive (HR+) BC. It has been hypothesized that peptide growth factor signaling and hormone signaling pathways interact and dual targeting of these pathways results in therapeutic synergy. We report a blinded analysis of HER-2, ER, and progesterone receptor (PR) expression for patients (pts) with HR+ MBC at first diagnosis or post-adjuvant relapse and response to Lap + Let versus Let. METHODS: 1286 pts were randomized 1:1 to 2.5 mg Let daily plus either 1500 mg Lap daily or placebo. The primary endpoint was PFS in HR+, HER-2+ MBC pts; secondary endpoints included PFS in the intent-to-treat population. Blinded, centralized commerical laboratory analysis of archived tumor tissue for HER-2 (IHC and/or FISH) and academic laboratory semi-quantitative analysis of ER/PR (IHC, H-score) was performed and correlated with clinical outcome. RESULTS: In 219/1286 (17%) HER-2+ (FISH+ or IHC3+) pts, a significant improvement in median PFS was observed for Lap + Let versus Let (8.2 v 3.0 mos, HR = 0.71, 95% CI 0.53, 0.96, p = 0.019). No significant difference in median PFS was seen in 952 (74%) HER-2-negative pts (13.4 v 13.7 mos, HR = 0.90, 95% CI 0.77, 1.05, p = 0.188). 821/952 (86%) HER-2-negative pts had tissue available for quantitative ER and PR analysis. Analysis of ER and PR by quartile identified a subgroup of HER-2-negative pts that benefitted from adding Lap to Let. Pts with the lowest quartile of ER expression (H-score <160, n = 207) had a significant improvement in median PFS (13.6 mos v 6.6 mos, HR = 0.65, 95% CI 0.47, 0.9, p < 0.005). Pts with higher levels of ER did not significantly benefit from adding Lap to Let. Analysis of PR expression did not identfiy a subgroup that benefited from Lap. CONCLUSIONS: Pts with HER-2-negative, ER+ MBC and low ER expression may benefit from the addition of lap to let. Additional analyses of EGFR, other biomarkers, and prior hormone therapy will be presented. [Table: see text]..

PURPOSE: Cross-talk between human epidermal growth factor receptors and hormone receptor pathways may cause endocrine resistance in breast cancer. This trial evaluated the effect of adding lapatinib, a dual tyrosine kinase inhibitor blocking epidermal growth factor receptor and human epidermal growth factor receptor 2 (HER2), to the aromatase inhibitor letrozole as first-line treatment of hormone receptor (HR) -positive metastatic breast cancer (MBC). PATIENTS AND METHODS: Postmenopausal women with HR-positive MBC were randomly assigned to daily letrozole (2.5 mg orally) plus lapatinib (1,500 mg orally) or letrozole and placebo. The primary end point was progression-free survival (PFS) in the HER2-positive population. Results In HR-positive, HER2-positive patients (n = 219), addition of lapatinib to letrozole significantly reduced the risk of disease progression versus letrozole-placebo (hazard ratio [HR] = 0.71; 95% CI, 0.53 to 0.96; P = .019); median PFS was 8.2 v 3.0 months, respectively. Clinical benefit (responsive or stable disease >or= 6 months) was significantly greater for lapatinib-letrozole versus letrozole-placebo (48% v 29%, respectively; odds ratio [OR] = 0.4; 95% CI, 0.2 to 0.8; P = .003). Patients with centrally confirmed HR-positive, HER2-negative tumors (n = 952) had no improvement in PFS. A preplanned Cox regression analysis identified prior antiestrogen therapy as a significant factor in the HER2-negative population; a nonsignificant trend toward prolonged PFS for lapatinib-letrozole was seen in patients who experienced relapse less than 6 months since prior tamoxifen discontinuation (HR = 0.78; 95% CI, 0.57 to 1.07; P = .117). Grade 3 or 4 adverse events were more common in the lapatinib-letrozole arm versus letrozole-placebo arm (diarrhea, 10% v 1%; rash, 1% v 0%, respectively), but they were manageable. CONCLUSION: This trial demonstrated that a combined targeted strategy with letrozole and lapatinib significantly enhances PFS and clinical benefit rates in patients with MBC that coexpresses HR and HER2..

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To date, there are no standard guidelines for treating patients with ipsilateral breast tumor recurrence (IBTR). Current practice is to resect the recurrence with a radical intent followed possibly by radiotherapy if the patient has not received this before, but the role of further adjuvant medical (hormone or chemotherapy) therapy remains undefined. Currently Phase III trials are underway to answer this question. In this review, we will focus on published data relating to IBTR and discuss recent trials. The results from the Phase III trials will not be available for sometime. At the time of IBTR, it is reasonable to change the endocrine therapy with indirect evidence from sequencing of impact on outcome. There is currently no conclusive evidence to suggest that further adjuvant chemotherapy post loco-regional recurrence impacts on survival, though the use of noncross-resistant chemotherapy drugs may make sense in those at highest risk. Biopsy at IBTR is helpful to distinguish whether it is a true recurrence or a new primary tumor and receptor phenotyping may be helpful for HER2. Future trials in IBTR need to address the following issues: to be able to distinguish between true recurrence and new primary (consensus required on definitions); pathologic processing relating to margins needs to be standardized (1 or 5 mm wide specimens); documentation of the pattern of IBTR in relation to each histopathologic subtype and methods used for pathologic examination by centers. Regional nodal recurrence including supraclavicular node recurrence is not dealt with in this review..

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PURPOSE: Inflammatory breast cancer (IBC) is one of the most aggressive forms of breast cancer. Lapatinib, an oral reversible inhibitor of epidermal growth factor receptor (EGFR) and human EGFR 2 (HER-2), demonstrated clinical activity in four of five IBC patients in phase I trials. We conducted a phase II trial to confirm the sensitivity of IBC to lapatinib, to determine whether response is HER-2 or EGFR dependent, and to elucidate a molecular signature predictive of lapatinib sensitivity. PATIENTS AND METHODS: Our open-label multicenter phase II trial (EGF103009) assessed clinical activity and safety of lapatinib monotherapy in patients with recurrent or anthracycline-refractory IBC. Patients were assigned to cohorts A (HER-2-overexpressing [HER-2+]) or B(HER-2-/EGFR+) and fresh pretreatment tumor biopsies were collected. RESULTS: Forty-five patients (30 in cohort A; 15 in cohort B) received lapatinib 1,500 mg once daily continuously. Clinical presentation and biomarker analyses demonstrated a tumor molecular signature consistent with IBC. Lapatinib was generally well tolerated, with primarily grade 1/2 skin and GI toxicities. Fifteen patients (50%) in cohort A had clinical responses to lapatinib in skin and/or measurable disease (according to Response Evaluation Criteria in Solid Tumors) compared with one patient in cohort B. Within cohort A, phosphorylated (p) HER-3 and lack of p53 expression predicted for response to lapatinib (P < .05). Tumors coexpressing pHER-2 and pHER-3 were more likely to respond to lapatinib (nine of 10 v four of 14; P = .0045). Prior trastuzumab therapy and loss of phosphate and tensin homolog 10 (PTEN) did not preclude response to lapatinib. CONCLUSION: Lapatinib is well tolerated with clinical activity in heavily pretreated HER-2+, but not EGFR+/HER-2-, IBC. In this study, coexpression of pHER-2 and pHER-3 in tumors seems to predict for a favorable response to lapatinib. These findings warrant further investigation of lapatinib monotherapy or combination therapy in HER-2+ IBC..

AIMS: To evaluate the efficacy and toxicity of a combination of intravenous vinorelbine and 5-fluorouracil (5-FU) given by continuous infusion in the treatment of metastatic breast cancer previously treated with anthracyclines and taxanes. MATERIALS AND METHODS: Sixty-one patients with metastatic breast cancer were treated with intravenous vinorelbine 30 mg/m2 on days 1 and 8 of each 21-day cycle together with 5-FU 200 mg/m2/day by continuous infusion. All had previously been treated with an anthracycline and 41% had also been previously treated with a taxane. All had normal haematological, renal and hepatic function and all but three had an Eastern Cooperative Oncology Group performance score of 2 or better. RESULTS: The overall response rate by World Health Organization criteria was 46% (28 patients); excluding nine non-evaluable patients gave a response rate of 54%. In patients who had previously been treated with both an anthracycline and a taxane, a response rate of 50% was observed (12 of 24 patients). Severe toxicity was uncommon, as was toxicity attributable to infusional 5-FU. Myelosuppression was rarely severe, but was common and led to delay or dose reduction in 38% of treatments. Eleven patients (18%) were admitted with fever and/or neutropenia and one patient died. The median received dose intensity was vinorelbine 16 mg/m2/week and 5-FU 143 mg/m2/day. CONCLUSIONS: The combination of vinorelbine and infusional 5-FU is active in metastatic breast cancer, including in patients previously treated with an anthracycline and a taxane. Toxicity is generally manageable, but myelosuppression is significant at this dose regimen. Recommended doses for routine clinical use are 5-FU 200 mg/m2/day and intravenous vinorelbine 30 mg/m2 days 1 and 15 on a 28-day cycle..

BACKGROUND: This study assessed the clinical efficacy of the farnesyltransferase inhibitor, tipifarnib, combined with letrozole in patients with advanced breast cancer and disease progression following antiestrogen therapy. PATIENTS AND METHODS: Postmenopausal women with estrogen-receptor-positive advanced breast cancer that had progressed after tamoxifen were given 2.5 mg letrozole once daily and were randomly assigned (2:1) to tipifarnib 300 mg (TL) or placebo (L) twice daily for 21 consecutive days in 28-day cycles. The primary endpoint was objective response rate. RESULTS: Of 120 patients treated with TL (n = 80) or L (n = 40), 113 were evaluable for response. Objective response rate was 30% (95% CI; 20-41%) for TL and 38% (95% CI; 23-55%) for L. There was no significant difference in response duration, time to disease progression or survival. Clinical benefit rates were 49% (TL) and 62% (L). Tipifarnib was generally well tolerated; a higher incidence of drug-related asymptomatic grade 3/4 neutropenia was observed for TL (18%) than for L (0%). Tipifarnib population pharmacokinetics were similar to previous studies, with no significant difference in trough letrozole concentrations between the TL and L groups. CONCLUSIONS: Adding tipifarnib to letrozole did not improve objective response rate in this population of patients with advanced breast cancer..

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Acquired resistance to endocrine therapies remains a major clinical obstacle in hormone-sensitive breast tumors. We used an MCF-7 breast tumor cell line (Tam(R)-1) resistant to tamoxifen to investigate this mechanism. We demonstrate that Tam(R)-1 express elevated levels of phosphorylated AKT and MAPK3/1-activated RPS6KA2 compared with the parental MCF-7 cell line (MCF-7). There was no change in the level of total ESR between the two cell lines; however, the Tam(R)-1 cells had increased phosphorylation of ESR1 ser(167). SiRNA blockade of AKT or MAPK3/1 had little effect on ESR1 ser(167) phosphorylation, but a combination of the two siRNAs abrogated this. Co-localization studies revealed an association between ERBB2 and ESR1 in the Tam(R)-1 but not MCF-7 cells. ESR1 was redistributed to extranuclear sites in Tam(R)-1 and was less transcriptionally competent compared with MCF-7 suggesting that nuclear ESR1 activity was suppressed in Tam(R)-1. Tamoxifen resistance in the Tam(R)-1 cells could be partially overcome by the ERBB2 inhibitor AG825 in combination with tamoxifen, and this was associated with re-localization of ESR1 to the nucleus. These data demonstrate that tamoxifen-resistant cells have the ability to switch between ERBB2 or ESR1 pathways promoting cell growth and that pharmacological inhibition of ERBB2 may be a therapeutic strategy for overcoming tamoxifen resistance..

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Mortality rates for breast cancer are improving in most countries. Life expectancy is also improving, and as age is the major risk factor for the development of breast cancer, we sought to determine whether survival of elderly women with breast cancer has improved over the past 20 years in our institution. In a retrospective study using a prospectively maintained database, we identified 950 women aged > or =70 years diagnosed with breast cancer between 1980 and 2000. Overall survival of patients was compared between two different time cohorts--those diagnosed from 1980 to 1990 and from 1991 to 2000--and between three age cohorts, 70-74, 75-79, and 80+ years. In all age groups, advanced stage, the need for mastectomy, and having chemotherapy were associated with a worse outcome on univariate analysis. Endocrine therapy (tamoxifen) was given to 60-70% of all age groups. After adjustment for clinical stage, we found no significant improvement in survival between the two time cohorts in any age groups. Compared with an age-matched group in the general population, these elderly breast cancer patients have a 62% increased risk of death. The results are likely to reflect lack of data to promote treatment guidelines. More clinical trials for older women are needed, if the benefits of recent advances in the management of this disease are to be extended to the over 70s. These data should, however, act as a benchmark for future audits..

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PURPOSE: Human epidermal growth factor receptor 2 (HER-2) expression is associated with increased risk of high-grade disease, nodal metastasis, and absence of estrogen receptors (ERs) in early breast cancer. We tested interactions between ER and HER-2 to determine if they may modulate breast cancer nodal metastasis and proliferation. PATIENTS AND METHODS: Tumors from the Cancer Research UK Taxotere as Adjuvant Chemotherapy phase III trial were tested for HER-2 using current diagnostic procedures. ER status, progesterone status, clinicopathologic characteristics, and patient age were included in a logistic regression analysis to identify associations with HER-2 status (positive v negative). RESULTS: A total of 841 (23.6%) of 3,565 samples were HER-2 positive (3+ by immunohistochemistry or positive by fluorescent in situ hybridization). ER-negative tumors were more likely to be HER-2 positive than were ER-positive tumors (odds ratio [OR] = 1.87, ER negative v ER positive; P < .001). For ER-positive tumors, risk of HER-2 positivity increased by grade (OR = 7.6, grade 3 v grade 1; P < .001) but not nodal status (OR = 1.3, four or more positive nodes v node negative; P = .08). Conversely, ER negative node-positive tumors were markedly more frequently HER-2 positive than node-negative cases (OR = 3.05, four or more positive nodes v node negative; P < .001) but independent of grade (OR = 0.82, grade 3 v grade 1; P = .76). CONCLUSION: In early breast cancer patients selected for cytotoxic chemotherapy, we identified significant interactions between HER-2 and ER expression that correlate with tumor pathology. In ER-positive breast cancers, HER-2 expression correlates with grade, not nodal metastasis. In ER-negative breast cancers, HER-2 expression correlates with increased nodal positivity, not grade. ER and HER-2 expression may modify tumor pathology via ER/HER-2-mediated cross talk..

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Patients with metastatic breast cancer (MBC) are increasingly offered third line chemotherapy. We have reviewed the response rate (RR), time to progression (TTP) and survival of 149 patients in this setting and have investigated factors that influence their outcome. The RR, TTP and survival were 30%, 4 and 8 months, respectively, and should serve as a benchmark for future studies. Response to previous chemotherapy was the only independent variable predicting RR, TTP and survival, p=0.025, 0.04 and 0.004, respectively. Thirty-two percent of patients did not respond to the first two lines of chemotherapy and had a lower RR and a significantly shorter TTP and survival. In conclusion, third line chemotherapy for MBC is sometimes effective in patients who have responded to previous chemotherapy. Patients who do not respond to the first two lines of chemotherapy should be considered for clinical trials or supportive care..

Sixty-three patients received capecitabine at 1000 mg/m2 twice daily every 2 out of 3 weeks as first-line treatment for advanced disease at our institution. Forty-five patients (71%) had previously received adjuvant or neoadjuvant chemotherapy. The median number of capecitabine cycles administered was 5(1-40). Forty-eight patients had measurable disease with response rate (RR) of 29%. The median time to progression (TTP) was 18(2-122) weeks. Seven patients (11%) had TTP of >1 yr, four of whom received more than 10(24-40) cycles of capecitabine. Thirty-seven percent of patients still needed dose reductions. Our retrospective audit is consistent with a previously published study which used a higher starting dose of capecitabine as first-line chemotherapy. For a subgroup of patients, capecitabine can result in a long TTP with minimal toxicity. The benefit of continuing capecitabine beyond a fixed number of cycles should be investigated further. Schedules using even lower doses of capecitabine for longer periods may also be of interest..

A greater understanding of the pathogenesis of malignancy has led to the development of novel therapies designed to target aberrant molecular pathways that characterize and distinguish cancer cells from normal tissue. Small molecules are being designed to interfere with specific steps along the deregulated signaling cascade from the cytoplasmic membrane to the nucleus. Viable targets include growth factor receptors and their downstream second messengers, modulators of the cell cycle or apoptosis, regulators of protein trafficking and degradation, and transcription regulators. This review will discuss the small molecule signal transduction inhibitors in various stages of development and address the strategic issues relating to clinical trial design with these novel targeted agents..

Cross-talk between receptor tyrosine kinases and estrogen receptor is at least partly responsible for the development of acquired resistance to endocrine therapies. Hence, targeting receptor tyrosine kinases and their downstream partners with inhibitors/antagonists may reverse this resistance. Although ras mutations are rare in breast cancer (2%), aberrant function of Ras signal transduction pathways is common. We therefore investigated the efficacy of the farnesyltransferase inhibitor (FTI) R115777 (tipifarnib) in combination with tamoxifen in MCF-7 human breast cancer models both in vitro and in vivo. There was a synergistic antiproliferative interaction between R115777 and 4-hydroxy-tamoxifen in vitro as calculated by median effect analysis. The combination resulted in a significantly greater G(1) arrest than either drug alone and this was associated with marked inhibition of cyclin D1 and induction of the cell cycle inhibitor p27(kip1). Combining R115777 with either tamoxifen or estrogen withdrawal in vivo produced a significantly greater inhibition of tumor growth and lower xenograft cell proliferation than either therapy alone. These results suggest that the combination of this FTI with endocrine therapy may be of therapeutic benefit in the treatment of breast cancer. Enhanced G1 arrest due to modulation of cell cycle regulatory proteins may be the underlying mechanism for the positive interaction between FTIs and tamoxifen..

Improving endocrine responsiveness and preventing the development of resistance is the goal of many current strategies that are looking to combine aromatase inhibitors with novel drugs that target various pathways in estrogen receptor (ER) positive breast cancer. Pre-clinical models of acquired resistance to aromatase inhibitors have suggested an increase in several signaling pathways including peptide growth factor signaling (EGFR, HER2) and activation of the mTOR signaling pathway. These may result in associated 'cross-talk' activation of ER-dependent gene transcription, such that dual blockade of ER together with other signaling pathways has become a logical approach to improve endocrine responsivness. Clinical strategies with aromatase inhibitors are looking to prevent activation of these pathways either through combination with the selective ER downregulator fulvestrant, or with various signal transduction inhibitors (STIs) including monoclonal antibodies (trastuzumab), small molecule tyrosine kinase inhibitors (TKIs) against EGFR or HER2 (lapatinib, gefitinib) and mTOR antagonists (temsirolimus). Early clinical data have emerged this year for some of these approaches with mixed results. This article reviews the rationale for these strategies, and discusses the lessons that need to be learnt if we are to successfully integrate these new drugs with aromatase inhibitors in the clinic..

A greater understanding of the biological mechanisms responsible for de novo and acquired endocrine resistance has led to the rational design of clinical trials exploring the benefit of combining hormonal therapies with novel biological agents in an effort to enhance the efficacy of ER+ breast cancer treatment. These studies are increasingly including parallel biological analyses to elucidate the molecular characteristics of those tumors that are most likely to respond to specific targeted/endocrine combinations in an effort to develop a tailored approach to the management of individual patients. Unfortunately despite encouraging preclinical data, some of these combinations have yielded disappointing results in the clinical setting. This article will review the results of clinical trials of endocrine/biological combinations conducted in early and advanced breast cancer as well as provide an update on ongoing studies..

Enhancing the benefit of endocrine therapy by overcoming de novo or acquired resistance remains an important goal in systemic breast cancer therapy. Progress continues to be made in elucidating the molecular pathways by which estrogen receptor-positive breast cancer cells escape from endocrine therapy. The increasing recognition of the roles of epidermal growth factor receptor (EGFR) and human EGFR2 in cross-talk activation of estrogen receptor signaling has led to studies aimed at identifying whether small-molecule tyrosine kinase inhibitors targeted against these receptors give additive or synergistic effects when combined with endocrine agents. Activation of the phosphatidylinositol-3-OH kinase/Akt pathway has also been associated with resistance to either tamoxifen or estrogen deprivation, and preclinical studies have shown that the mammalian target of rapamycin antagonist temsirolimus can restore endocrine sensitivity in breast cancer cells. Randomized phase II trials of aromatase inhibitors combined with EGFR/human EGFR2 tyrosine kinase inhibitors or mammalian target of rapamycin antagonists have been completed in both the neoadjuvant and advanced breast cancer settings. Larger phase III trials with both approaches are now in progress and have been powered to detect whether either strategy can significantly prolong time to disease progression compared with endocrine therapy alone. The correlation of molecular and clinical results from these ongoing studies will be important to establish appropriate biological variables for selecting those patients who may benefit most from this combined approach..

Lapatinib is an oral dual tyrosine kinase inhibitor that targets epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor-2 (HER2), both frequently overexpressed in human cancer. Preclinical data have shown that lapatinib is a potent and selective inhibitor of the tyrosine kinase domain of EGFR and HER2, and tumor cells that overexpress these receptors are growth inhibited by lapatinib both in vitro and in vivo. Phase I clinical trials have shown that lapatinib is well tolerated, with mild diarrhea and rash the most frequent toxicities, and early evidence of clinical efficacy has been reported especially in HER2-positive breast cancer. Phase II studies have shown activity for lapatinib in trastuzumab-refractory breast cancer either alone or in combination with trastuzumab. When used as first-line monotherapy for advanced breast cancer, objective tumor responses have been seen in 28% of patients with untreated HER2-positive advanced breast cancer. An extensive phase III program in advanced breast cancer is now in progress both for refractory disease and as first-line therapy in combination with chemotherapy with and without trastuzumab, and with endocrine therapy. Phase II studies have also been conducted in a variety of other tumors, including renal cell cancer. Parallel biomarker studies are starting to elucidate predictive molecular phenotypes that may indicate likelihood of response to lapatinib, and these may direct future trials with this oral tyrosine kinase inhibitor..

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BACKGROUND: Docetaxel has significant activity in metastatic breast cancer and weekly schedules are associated with less myelosuppression than 3-weekly schedules. We evaluated the toxicity and the activity of weekly docetaxel in anthracycline-pretreated patients. PATIENTS AND METHODS: A total of 42 patients were studied. Treatment consisted of docetaxel 35 mg/m2 weekly as a 30-min infusion for 6 weeks followed by a 2-week rest, with dexamethasone 8 mg i.v. pre-medication and 4 mg orally 12-hourly for 48 h following treatment. RESULTS: The median age of the patients was 53 years (range 34-74). Twenty-six (62%) patients had received prior chemotherapy for advanced disease. Patients received a median 10 weeks of treatment (range 1-24). 11 had a partial response (ORR 26%; 95% CI 13-39%), five of whom had relapsed <12 months since the end of previous anthracycline-based chemotherapy. In addition six patients (14%) had stable disease for >16 weeks. Myelosuppression was rare with only 2 patients (5%) experiencing grade 3 neutropenia (no grade 4 neutropenia). Non-haematological grade III toxicities were as follows: fatigue 17%, neuropathy 0%, hyperlacrimation 5%, stomatitis 7%, diarrhoea 14%, and cutaneous toxicity 19%. Skin toxicity consisted of limb/palmar-plantar erythematous reactions, or fixed-plaque erythrodysaesthesia. CONCLUSIONS: Weekly docetaxel has moderate activity in women with anthracycline pre-treated breast cancer. Although the level of myelosuppression is lower than 3-weekly regimens, this weekly regimen cannot be recommended due to the significant non-haematological toxicities associated with the treatment..

In breast cancer, there is an increasing recognition of the pivotal role played by the epidermal growth factor receptor (EGFR) and HER2 together with the various downstream signal transduction pathways, in particular the Ras/Raf/Mek/erk1/2 pathway that regulates cell proliferation together with the phosphatidylinositol-3-OH kinase (PI3K)/Akt/mTOR pathway that is implicated in cell survival. While monoclonal antibodies and small molecule tyrosine kinase inhibitors targeted against EGFR/HER2 are now being used for breast cancer therapy, there is considerable interest in also targeting the critical downstream pathways that cells may remain dependent upon. Activation of these downstream pathways in breast cancer may be associated with resistance to either conventional endocrine or cytotoxic therapies or, indeed, lack of response to EGFR/HER2-targeted approaches. Farnesyltransferase inhibitors (FTIs) were initially developed to target Ras activation, although their mechanism of action may be more nonspecific. Trials in breast cancer have been completed with FTIs alone or in combination with endocrine or cytotoxic therapy. Activation of the PI3K/Akt pathway has also been associated with resistance to either tamoxifen or estrogen deprivation, and preclinical studies have shown that the mTOR antagonists can restore endocrine sensitivity in breast cancer cells. Randomized phase II/III trials of aromatase inhibitors combined with mTOR antagonists are in progress and have been powered to detect whether combined therapy can significantly prolong time to disease progression compared to endocrine therapy alone. Finally, preclinical experiments are now investigating whether downstream agents should be combined with upstream EGFR/HER2 therapies to produce maximal blockade of vertical signal transduction pathways. Subsequent trials will be needed to see whether combinations of novel STIs are well tolerated and how they may further enhance clinical benefit in breast cancer..

We aim to investigate the incidence, patterns and timing of brain metastases in advanced breast cancer patients who have previously received trastuzumab. Eighty-seven patients who had received trastuzumab for advanced breast cancer from November 1999 to September 2003 at the Royal Marsden Hospital were assessed. With a median follow-up period of 11 months from commencing trastuzumab, 23 patients developed brain metastases (30% at 1 year; 95% CI 58-82%). Among 57 patients who had clinical benefits on trastuzumab, 12 (21%) patients developed first disease progression in brain with 75% of them had isolated CNS progression. Moreover, among patients who received trastuzumab as first line treatment, isolated brain metastases were the initial site of progression in 17% patients. Nearly all patients developed parenchymal brain disease. This study shows brain metastases are common phenomenon in HER2 positive advanced breast cancer patients receiving trastuzumab and also may implicate the brain as a sanctuary site for early relapse in this patient cohort..

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There is an increasing rationale for effective combinations of endocrine therapy with novel drugs that target aberrant signal transduction pathways in estrogen receptor (ER) positive breast cancer. Prolonged endocrine therapy can be associated with an acquired increase in peptide growth factor signaling (EGFR, HER2), together with cross-talk activation of ER-dependent gene transcription and cell growth that leads to endocrine resistance. Current approaches to target these pathways include both the selective ER downregulator fulvestrant, and various signal transduction inhibitors (STIs). Fulvestrant can overcome resistance to tamoxifen (TAM-R) and long-term estrogen deprivation (LTED-R) in experimental models by reducing ER expression, and represents a current option for post-menopausal women with endocrine resistant ER+ve breast cancer. Emerging data suggest that fulvestrant's effect may be greater when combined with estrogen deprivation, and several phase III trials are assessing fulvestrant combined with aromatase inhibitors (AIs). Small molecule STIs such as tyrosine kinase inhibitors (TKIs), farnesyltransferase inhibitors (FTIs) and mTOR antagonists are also active in breast cancer. Pre-clinical data suggest that combined endocrine/STI therapy may result in greater growth inhibition than either therapy alone, and thus delay emergence of resistance. Several clinical trials are now examining STIs combined with AIs both in the tamoxifen-resistant and first-line advanced breast cancer setting, while pre-surgical studies are investigating the efficacy of combined endocrine/STI therapy utilising biological primary endpoints. This article reviews the pre-clinical rationale for this strategy and the clinical trials in this area..

Aromatase inhibitors are rapidly becoming the first choice for hormonal treatment of steroid receptor positive breast cancer in postmenopausal women. An understanding of the resistance mechanisms to these agents is, therefore, important for the appropriate delivery of treatment to responsive patients and the rational development of new agents targeted at the resistance pathways. De novo resistance appears to be a quantitative rather than qualitative phenomenon with virtually all oestrogen receptor positive tumours showing an anti-proliferative response to the aromatase inhibitor anastrozole. While the expression of type 1 growth factor receptors reduces response to tamoxifen this appears to have little detrimental effect on response to aromatase inhibitors. Studies of acquired resistance in vitro have indicated that acquisition of hypersensitivity to oestrogenic stimulation is a key mechanism that is dependent on enhanced cross-talk of growth factor and oestrogen signaling pathways. Collection of resistant biopsy tissues from patients is important to determine if this mechanism is clinically relevant..

The knowledge that steroids play a pivotal role in the development of breast cancer has been exploited clinically by the development of endocrine treatments. These have sought to perturb the steroid hormone environment of the tumour cells, predominately by withdrawal or antagonism of oestrogen. Unfortunately, the beneficial actions of existing endocrine treatments are attenuated by the ability of tumours to circumvent the need for steroid hormones, whilst in most cases, retaining the nuclear steroid receptors. The mechanisms involved in resistance to estrogen deprivation are of major clinical relevance for optimal treatment of breast cancer patients and the development of new therapeutic regimes. We have shown that long-term culture of MCF7 cells in medium depleted of oestrogen (LTED) results in hypersensitivity to oestradiol (E2) coinciding with elevated levels of both ERalpha phosphorylated on Ser(118) and ERK1/ERK2. Our data suggest elevated ERK1/ERK2 activity results wholly or in part from enhanced ERBB2 expression in the LTED cells. These cells showed greater sensitivity to the tyrosine kinase inhibitor ZD1839 in both ERalpha-mediated transcription and growth assays compared with the wt-MCF7. Similarly the MEK inhibitor U0126 decreased basal ERalpha-mediated transcription and proliferation in the LTED cells by 50% and reduced their sensitivity to the proliferative effects of E2 10-fold, whilst having no effect on the wild type (wt). However, complete suppression of ERK1/ERK2 activity in the LTED cells did not inhibit ERalpha Ser(118) phosphorylation suggesting that the cells remained ligand-dependent. This was further confirmed by the increased sensitivity of the LTED cells to the growth suppressive effects of ICI 182,780 and suggested that the LTED cells remained wholly or partially dependent on oestrogen receptor (ER)/oestrogen responsive elements directed growth. These findings suggest that treatments targeted at growth factor signalling pathways may be useful in patients acquiring resistance to oestrogen deprivation with aromatase inhibitors and that the pure anti-oestrogen ICI 182,780 may also be effective by blocking or destabilizing ER and hence disrupting cross-talk..

De novo resistance to endocrine therapy is a near-universal feature of oestrogen receptor (ER)- negative breast cancer. Although many ER-positive breast cancers also show no response to tamoxifen or aromatase inhibitors on objective clinical grounds the large majority show reduced proliferation indicating that some oestrogen dependence is present in almost all ER-positive breast cancer. In neoadjuvant studies HER2 positivity is associated with poor response rates to tamoxifen but not aromatase inhibitors, consistent with preclinical models. Acquired resistance to tamoxifen is associated with decreases in ER positivity but most recurrent lesions remain ER-positive. A small proportion of these show increased HER2 expression and in these patients increased phospho-p38 may contribute to the tamoxifen-resistant phenotype. There is an unfortunate paucity of clinical and biological data on acquired resistance to aromatase inhibitors..

Acquired resistance to endocrine therapy in breast cancer is associated with an increase in peptide growth factor signaling that results in cross-talk activation of the estrogen receptor (ER). Small molecule signal transduction inhibitors (STIs) can target components of these intracellular pathways, and may prove effective in anticancer therapy. However, early phase II clinical trials with various STIs as monotherapy in advanced breast cancer have shown only a modest level of efficacy for these intracellular inhibitors. Preclinical data suggest that combinations of tamoxifen with STIs may provide significantly greater growth inhibition than either therapy alone, and, furthermore, may delay the emergence of endocrine resistance. There are now several trials assessing the efficacy of combinations of small molecule tyrosine kinase inhibitors (TKIs), such as gefitinib and lapatinib, with either tamoxifen or aromatase inhibitors both in the second-line, endocrine-resistant and first-line, hormone-sensitive setting. Similar trials continue with both farnesyltransferase inhibitors (FTIs) and mTOR antagonists, where there are strong preclinical data to suggest additive or synergistic effects for either of these agents in combination with endocrine therapies. Biomarker studies in the presurgical setting are also being utilized as an alternative approach to investigate whether combined endocrine/STI therapy is an effective clinical strategy. This article reviews some of the preclinical evidence supporting this strategy, together with the current status of clinical trials in this area..

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This phase II study assessed the clinical efficacy and tolerability of a combination of mitomycin C, vinblastine and cisplatin in patients with metastatic breast cancer (MBC) previously treated with chemotherapy. A total of 87 patients with MBC, most of whom had been exposed to anthracyclines (92%) and/or taxanes (29%) in the adjuvant and/or metastatic setting, were treated with mitomycin C (8 mg m(-2) day 1 cycles 1, 2, 4 and 6), vinblastine (6 mg m(-2) day 1) and cisplatin (50 mg m(-2) day 1) repeated each 21 days for a maximum of six cycles. The overall response rate (ORR) was 32% (95% CI: 22-42%) with 31% partial response (PR) and one complete response (CR). Stable disease (SD) rate was 21% (95% CI: 12-29%). There was no statistically significant difference in the ORR when MVP was given as the first-line treatment for MBC vs second or subsequent line (38 vs 30%, P=0.6), or between patients with an early (<6 months) vs late (>6 months) relapse post-anthracyclines (30 vs 52%, P=0.3). Toxicity profile was mild. This platinum-based chemotherapy is an effective, well-tolerated and low-cost regimen for patients with MBC, including those pretreated with anthracyclines..

There is an increasing rationale to develop effective combinations of endocrine agents with novel therapeutics that target aberrant signal transduction pathways in estrogen receptor-positive breast cancer. Acquired resistance to endocrine therapy is associated with an increase in peptide growth factor signaling that results in crosstalk activation of estrogen receptor, and various signal transduction inhibitors (STI) can target these pathways to inhibit hormone-resistant growth. In experimental models of hormone-sensitive breast cancer, combinations of endocrine agents with STIs provide significantly greater growth inhibition than either alone, delaying the emergence of resistance. There are now several trials assessing the efficacy of combinations of tyrosine kinase inhibitors with various endocrine agents in the tamoxifen-resistant/second-line setting, together with five randomized phase II/III trials in the first-line setting. Similar work is ongoing with both farnesyltransferase inhibitors and mTOR antagonists where there are strong preclinical data to suggest additive or synergistic effects for either of these agents in combination with tamoxifen or estrogen deprivation therapies. More recently, presurgical studies with biological primary end points are being utilized as an alternative approach to investigate whether combined endocrine/STI therapy is a more effective strategy than endocrine therapy alone. This article reviews the rationale and current status of clinical trials in this area as well as the challenges that lie ahead for the development of these therapeutic combinations for breast cancer..

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The third-generation non-steroidal aromatase inhibitors (AIs) are challenging tamoxifen as treatments of choice for early and advanced breast cancer in postmenopausal women with estrogen receptor (ER)-positive disease. However, patients who initially respond to AIs eventually develop resistance to treatment and experience disease progression. To establish the optimal endocrine therapy following AI resistance, it is essential to understand the mechanisms that contribute to the loss of response. Data from in vitro models have suggested that acquired AI resistance is due to enhanced sensitization to low estrogen levels during long-term estrogen deprivation (LTED). Cross-talk between the ER and various growth-factor-receptor signaling pathways, including human epidermal growth factor receptor 2, and the insulin-like growth factor pathway, may also be implicated. Therefore, endocrine therapies that abolish estrogen signaling via removal of the ER could be effective in patients with AI-resistant disease. Fulvestrant ('Faslodex') is a new ER antagonist with no agonist effects that binds, blocks and degrades the ER. Due to its unique mode of action and lack of cross-resistance with existing treatments, fulvestrant is an effective therapeutic agent for use in sequential endocrine regimens. Fulvestrant has established efficacy in tamoxifen-resistant disease and there is a growing body of evidence demonstrating its efficacy in patients with AI-resistant disease. In preclinical models, MCF-7 cells undergoing LTED are refractory to tamoxifen but sensitive to fulvestrant, suggesting fulvestrant is a more appropriate choice following AI resistance. The steroidal AI, exemestane is also an option in non-steroidal AI-resistant disease. Clinical trials are underway to compare fulvestrant with exemestane as an appropriate therapy following the onset of AI resistance..

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Although tamoxifen has been an effective treatment for breast cancer, several novel anti-oestrogen compounds have been developed with a reduced agonist profile on breast and gynaecological tissues. These include selective oestrogen receptor modulators (SERMs; both 'tamoxifen-like' and 'fixed-ring' SERMs) and selective oestrogen receptor downregulators (SERDs), although none has been proved superior in efficacy to tamoxifen in various advanced breast cancer trials. Thus, many have questioned whether a need for SERMs in breast cancer still exists, although chemoprevention remains a possible niche setting. In contrast, SERDs may have useful efficacy following aromatase inhibitors because of their unique mechanism of action, and clinical trials to determine their optimal use or sequence are ongoing..

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Following relapse on endocrine therapy for advanced, hormone receptor-positive breast cancer, it is common for patients to experience responses to alternative endocrine agents. Fulvestrant ('Faslodex') is a new type of endocrine treatment--an oestrogen receptor (ER) antagonist with no agonist effects. Fulvestrant downregulates cellular levels of the ER resulting in decreased expression of the progesterone receptor. This unique mode of action means that it is important that fulvestrant is placed optimally within the sequence of endocrine therapies to ensure that patients gain maximum benefit. Fulvestrant has shown efficacy when used after progression on tamoxifen or anastrozole in postmenopausal women with advanced breast cancer. After progression on fulvestrant, subsequent endocrine treatments can produce responses in many patients, demonstrating that fulvestrant does not lead to crossresistance with other endocrine therapies. Responses to fulvestrant have also been observed in patients heavily pretreated with prior endocrine therapy. Fulvestrant is a versatile endocrine agent that may be integrated into the therapeutic sequence prior to, or subsequent to, other hormonal therapies, and represents a valuable additional antioestrogen for the treatment of postmenopausal women with advanced breast cancer..

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Idoxifene is a novel selective oestrogen receptor modulator (SERM) which had greater binding affinity for the oestrogen receptor (ER) and reduced agonist activity compared with tamoxifen in preclinical studies. In a randomized phase II trial in 56 postmenopausal patients with progressive locally advanced/metastatic breast cancer we assessed whether idoxifene showed evidence of activity compared with an increased 40 mg/day dose of tamoxifen in patients who had previously demonstrated resistance to the standard 20 mg/day dose of tamoxifen. Of 47 patients eligible for response (25 idoxifene, 22 tamoxifen), two partial responses and two disease stabilizations (SD) for >6 months were seen with idoxifene (overall clinical benefit rate 16%, 95% CI 4.5-36.1%). The median duration of clinical benefit was 9.8 months. In contrast, no objective responses were seen with the increased 40 mg/day dose of tamoxifen, although two patients had SD for 7 and 14 months (clinical benefit rate 9%, 95% CI 1.1-29.2%). Idoxifene was well tolerated and the reported possible drug-related toxicities were similar in frequency to those with tamoxifen (hot flushes 13% vs 15%, mild nausea 20% vs 15%). Endocrine and lipid analysis in both groups showed a similar significant fall in serum follicle-stimulating hormone and luteinizing hormone after 4 weeks, together with a significant rise in sex hormone binding globulin levels and 11% reduction in serum cholesterol levels. In conclusion, while idoxifene was associated with only modest evidence of clinical activity in patients with tamoxifen-resistant breast cancer, its toxicity profile and effects on endocrine/lipid parameters were similar to those of tamoxifen..

6044 Background: The MA17 study was a randomized double-blind placebo-controlled trial of 5 years of letrozole (Femara®) 2.5 mg/d in 5187 postmenopausal women (median age 62 yrs) with early breast cancer after 5 years of adjuvant tamoxifen. Due to significant improvement in disease-free survival with letrozole (92.8% vs 86.8%, P≤.001) and a trend toward an improvement in overall survival (96.0% vs 93.7%, P=.25), the study was unblinded at the first interim analysis (mean follow-up 2.4 years). The cost-effectiveness of extended adjuvant letrozole has not been examined. METHODS: A Markov model of the natural history of breast cancer (Karnon, 2002) was adapted to evaluate the cost-effectiveness of extended adjuvant letrozole 2.5 mg/d in postmenopausal women. Probabilities of disease progression (locoregional and distant recurrence, new contralateral tumor) and death were estimated using published results of the MA17 trial (Goss, 2003) and other published studies. Costs of letrozole therapy and other breast cancer care (surveillance, treatment of recurrence and new contralateral tumor, death) and utility values were estimated from published sources. Cost-effectiveness was calculated as the ratio of the difference (letrozole vs no treatment) in expected lifetime costs to the difference in life years (LYs) and quality-adjusted LYs (QALYs) respectively; 95% CIs were estimated by probabilistic sensitivity analysis. Costs, LYs, and QALYs were discounted at 3% annually. RESULTS: Letrozole therapy is estimated to result in an additional 0.53 LYs per patient (13.94 vs 13.41) and a similar gain in QALYs (12.49 vs 11.96). Expected lifetime costs of breast cancer care are estimated to be $9,350 greater with letrozole ($30,580 vs $21,240 with no treatment). Cost per LY gained with letrozole vs no treatment is $17,640 (95% CI $9,680 to $58,970). Cost per QALY gained is similar. CONCLUSIONS: Preliminary analyses based on published results of MA17 suggest that, compared with other generally-accepted treatments for early breast cancer (Earle, 2000), extended adjuvant letrozole is cost-effective while providing a 43% reduction in risk of recurrence. [Table: see text]..

Current systemic therapies for breast cancer are often limited by their nonspecific mechanism of action, unwanted toxicities on normal tissues, and short-term efficacy due to the emergence of drug resistance. However, identification of the molecular abnormalities in cancer, in particular the key proteins involved in abnormal cell growth, has resulted in development of various signal transduction inhibitor drugs as new treatment strategies against the disease. Protein farnesyltransferase inhibitors (FTIs) were originally designed to target the Ras signal transduction pathway, although it is now clear that several other intracellular proteins are dependent on post-translational farnesylation for their function. Preclinical data revealed that although FTIs inhibit the growth of ras-transformed cells, they are also potent inhibitors of a wide range of cancer cell lines that contain wild-type ras, including breast cancer cells. Additive or synergistic effects were observed when FTIs were combined with cytotoxic agents (in particular the taxanes) or endocrine therapies (tamoxifen). Phase I trials with FTIs have explored different schedules for prolonged administration, and dose-limiting toxicities included myelosuppression, gastrointestinal toxicity and neuropathy. Clinical efficacy against breast cancer was seen for the FTI tipifarnib in a phase II study. Based on promising preclinical data that suggest synergy with taxanes or endocrine therapy, combination clinical studies are now in progress to determine whether FTIs can add further to the efficacy of conventional breast cancer therapies..

The National Institute for Clinical Excellence (NICE), established in 1996 as a special Health Authority for England and Wales, provides the United Kingdom medical community with robust and reliable guidance on current "best practices" in medicine. Based on analyses of clinical efficacy, safety, and cost effectiveness, clinical guideline recommendations are developed in an attempt to standardize treatment of various diseases and medical conditions. To date, NICE has issued guidance for the use of three chemotherapeutic agents in the treatment of ovarian cancer: paclitaxel, topotecan, and pegylated liposomal doxorubicin. NICE guidance recommends surgery and adjuvant chemotherapy with paclitaxel/platinum combination therapy or platinum therapy alone as first-line treatment for ovarian cancer. NICE has also issued guidance recommending the use of topotecan or pegylated liposomal doxorubicin as second-line agents for the treatment of women with relapsed or refractory disease. Accounting for all available data, NICE guidance supports the appropriate roles of paclitaxel, topotecan, and pegylated liposomal doxorubicin in the treatment of advanced ovarian cancer..

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Arzoxifene (ARZ) is a selective estrogen receptor (ER) modulator with greater bioavailability than raloxifene which is being developed as treatment for breast cancer. We have used an in vivo model of hormone-sensitive breast cancer to study the growth-inhibitory and pharmacodynamic effects of ARZ in comparison with the most widely used antiestrogen, tamoxifen (TAM). We compared the abilities of ARZ and TAM to antagonize the estrogen (E2)-dependent growth of MCF-7 human breast cancer xenografts in oophorectomized athymic mice. At four different time points over 28 days, we studied their time-related pharmacodynamic effects on biomarkers of tumor growth (cell proliferation/death measured by Ki-67 and apoptosis scores), cell cycle activity (cyclin D1 and p27(kip1)), and hormone-regulated gene expression (ERalpha, progesterone receptor, and pS2). Although maximal growth inhibition was seen after E2 withdrawal, ARZ and TAM induced significant and similar inhibition of E2-stimulated tumor growth. Inhibition of growth was reflected by changes in the tumor growth index (ratio posttreatment/pretreatment Ki-67/apoptosis scores). ARZ and TAM resulted in a significant (P < 0.001) increase in ER expression and reduction in progesterone receptor expression, whereas changes in cyclin D1 score were inversely related to p27(kip1) score. A significant but delayed biological effect was observed with a 10-fold lower dose of ARZ. These results show that ARZ is an effective antagonist of E2-stimulated breast cancer growth with similar growth-inhibitory and pharmacodynamic effects to TAM in this model..

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Recent evidence suggests that common molecular adaptations occur during resistance to both tamoxifen and estrogen deprivation that use various signal transduction pathways, often involving cross-talk with a retained and functional estrogen receptor (ER) protein. There appear to be several different levels at which this cross-talk may occur, including peptide growth factor signaling via the type 1 tyrosine kinase growth factor receptor family [epidermal growth factor receptor (EGFR) and HER2], which may become up-regulated during endocrine treatment, ultimately being harnessed by cells to allow them hormone-independent growth. ER may remain involved in cell growth with ligand-independent phosphorylation and activation via different intracellular mitogen-activated protein kinases. ER may also become involved in non-nuclear estrogen-dependent signaling via interaction with the phosphatidylinositol 3'-kinase/Akt cell survival pathway or may interact with the stress-activated protein kinase/c-Jun-NH(2)-terminal kinase pathway. Understanding these mechanisms will permit the optimal integration of new signal transduction inhibitors (STIs) into breast cancer therapy. Preclinical approaches that have shown promise include the use of EGFR tyrosine kinase inhibitors for hormone-resistant breast cancer cells that are dependent on either EGFR or HER2 signaling. Likewise, farnesyl transferase inhibitors, mitogen-activated protein kinase inhibitors, and cell cycle inhibitors have all shown activity in experimental breast cancer models. Emerging data suggest that STIs may be more effective when given in combination with endocrine therapy either to overcome resistance or to prevent/delay emergence of the resistance phenotype. Clinical trials are in progress to determine the safety and optimal schedule for each of the various STIs, and studies of STIs in combination with aromatase inhibitors have commenced in breast cancer to see whether the therapeutic response to endocrine therapy can be enhanced further..

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Bristol-Myers Squibb is developing BMS-214662, a farnesyl transferase inhibitor, for the potential treatment of cancer. By October 2000, preclinical investigations were ongoing in Japan. By February 2001, the drug was in phase II trials in the US for pancreatic, head and neck, lung and colorectal cancers..

Current systemic cytotoxic therapies for cancer are limited by their nonspecific mechanism of action, unwanted toxicities on normal tissues and short-term efficacy due to the emergence of drug resistance. However, identification of the molecular abnormalities in cancer, in particular the key proteins involved in abnormal cell growth, has resulted in various signal transduction inhibitor drugs being developed as new treatment strategies against the disease. Protein farnesyltransferase inhibitors (FTIs) were originally designed to target the Ras signal transduction pathway, although it is now clear that several other intracellular proteins are dependent on post-translational farnesylation (addition of a 15-carbon farnesyl moiety) for their function. Preclinical data revealed that although FTIs inhibit the growth of ras-transformed cells, they are also potent inhibitors of a wide range of cancer cell lines, many of which contain wild type ras. While understanding the mechanism of action of FTIs remains an important research goal, three different FTIs have entered clinical development. Several Phase I trials with each drug have explored different schedules for prolonged administration, and dose-limiting toxicities (DLTs) have varied from myelosuppression, gastrointestinal toxicity and neuropathy. Evidence for anticancer efficacy has come from a number of Phase II studies, not necessarily in tumour types containing ras mutations, which were the initial target for these drugs. Perhaps the most promising use for FTIs will be in combination with conventional cytotoxic drugs, based on preclinical data suggesting synergy, particularly with the taxanes. Clinical combination studies are in progress, and larger Phase II/III clinical trials are planned to see if FTIs can add to the efficacy of conventional therapies..

The use of totally implantable venous devices (TIVDs) has revolutionised the care and quality of life of oncology patients. Although considered to be generally safe, catheter fracture is a rare but serious complication. The 'pinch-off' syndrome is caused by the compression of the catheter between the clavicle and first rib, and may lead to fracture and possible dislocation of the catheter. We report here the case history of two patients with metastatic breast cancer who developed the 'pinch-off' syndrome, first recognised by difficulty in line aspiration and pain during injection of the catheter. In one case, there was complete fracture with migration of the catheter tip to the right pulmonary artery. In both cases, the lines were removed without serious injury to the patient. All patients with TIVDs should be investigated for possible catheter fracture if they develop pain over the superior anterior chest wall and/or there is difficulty or pain during aspiration or injection..

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The rapid expansion in our knowledge of the molecular pathogenesis of cancer has created several opportunities for novel strategies in anti-cancer drug design and development. Recent developments have included a series of new endocrine therapies such as pure anti-oestrogens and selective oestrogen receptor modulators, and trials are in progress to determine their role in the sequence of therapies given the first-line role now occupied by the aromatase inhibitors. Novel cytotoxic drugs have been developed with an improved toxicity profile, including oral prodrugs that are activated within tumour cells, and liposomal delivery mechanisms for conventional drugs that reduce some of the systemic toxicities. There has been much success with monoclonal antibodies targeted against growth factor receptors, both as monotherapy and in enhancing the efficacy of cytotoxic drugs. A number of small molecule signal transduction inhibitors are in early stages of clinical development for breast cancer, including tyrosine-kinase inhibitors and farnesyl transferase inhibitors. Emerging pre-clinical evidence suggests that these drugs may best be used in combination with endocrine therapy. Other novel strategies that are being tested include vaccines and anti-angiogenesis drugs. As these new therapies evolve towards the clinic, the challenge to oncologists is whether their potential seen in the laboratory can be matched by further substantial improvements in clinical outcome..

The mechanisms involved in resistance to estrogen deprivation are of major importance for optimal patient therapy and the development of new drugs. Long term culture of MCF-7 cells in estrogen (E2)-depleted medium (long term estrogen deprivation; LTED) results in hypersensitivity to E2 coinciding with elevated levels of estrogen receptor (ER) alpha phosphorylated on Ser118 and MAPK, together with several of its downstream targets associated previously with ERalpha phosphorylation. Our data suggest elevated MAPK activity results from enhanced ERBB2 expression in the LTED cells versus the wild-type (wt), and treatment with the tyrosine kinase inhibitor ZD1839 revealed increased sensitivity in both transcription and proliferation assays. Similarly the MEK inhibitor U0126 decreased transcription and proliferation in the LTED cells and reduced their sensitivity to the proliferative effects of E2, while having no effect on the wt. However, the complete suppression of MAPK activity in the LTED cells did not inhibit ERalpha Ser118 phosphorylation suggesting that ER activity remained ligand-dependant. The LTED cells also expressed elevated levels of insulin-like growth factor-1R, and inhibition of phosphatidylinositol 3-kinase activity with LY294002 reduced basal ERalpha transactivation by 70% in the LTED cells compared with the wt. However, LY294002 had no effect on ERalpha Ser118 phosphorylation. These data suggest that although elevated levels of MAPK occur during LTED and influence the phenotype, this is unlikely to be the sole pathway operating to achieve adaptation..

OBJECTIVE: To review the evidence for the use of bisphosphonates to reduce skeletal morbidity in cancer patients with bone metastases. DATA SOURCES: Electronic databases, scanning reference lists, and consultation with experts and pharmaceutical companies. Foreign language papers were included. STUDY SELECTION: Included trials were randomised controlled trials of patients with malignant disease and bone metastases who were treated with oral or intravenous bisphosphonate compared with another bisphosphonate, placebo, or standard care. All trials measured at least one outcome of skeletal morbidity. RESULTS: 95 articles were identified; 30 studies fulfilled inclusion criteria. In studies that lasted > or = 6 months, compared with placebo bisphosphonates significantly reduced the odds ratio for fractures (vertebral 0.69, 95% confidence interval 0.57 to 0.84, P < 0.0001; non-vertebral 0.65, 0.54 to 0.79, P < 0.0001; combined 0.65, 0.55 to 0.78, P < 0.0001), radiotherapy (0.67, 0.57 to 0.79, P < 0.0001), and hypercalcaemia (0.54, 0.36 to 0.81, P = 0.003) but not for orthopaedic surgery (0.70, 0.46 to 1.05, P = 0.086) or spinal cord compression (0.71, 0.47 to 1.08, P = 0.113). The reduction in orthopaedic surgery was significant in studies that lasted over a year (0.59, 0.39 to 0.88, P = 0.009). Use of bisphosphonates significantly increased time to first skeletal related event but did not increase survival. Subanalyses showed that most evidence supports use of intravenous aminobisphosphonates. CONCLUSIONS: In people with metastatic bone disease bisphosphonates significantly decrease skeletal morbidity, except for spinal cord compression and increased time to first skeletal related event. Treatment should start when bone metastases are diagnosed and continue until it is no longer clinically relevant..

Fulvestrant (Faslodex) is an estrogen receptor (ER) downregulator under development by AstraZeneca for the potential treatment of breast cancer [172191], [237518], [314472], [349551]. In March 2001, an NDA was filed in the US for the second-line treatment of advanced breast cancer in postmenopausal women who have progressed on prior hormonal therapy [403574], [434825]; in December 2001, AstraZeneca was expecting to launch the compound in the US in thefirst half of 2002 [431887]. In August 2001, late-stage clinical trials were ongoing in Japan for breast cancer [422343]. Fulvestrant also has potential in the treatment of other estrogen-responsive tumors, such as uterine tumors [178081]. By 1997, fulvestrant was in phase II trials for uterine fibroids [272162], and by February 1999, it was reported that phase II trials for endometriosis were ongoing [314472], [336599]. However, no development has been reported for these indications since that time. In October 2001, Morgan Stanley expected launch in 2002, with estimated sales of $80 million in 2002 rising to $208 million in 2007 [429700]. Analysts at Lehman Brothers predicted in December 2001, that the product has a 90% chance of making it to market in 2002, with peak sales potential in this year of $800 million [434768]..

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Standard chemotherapy for advanced epithelial ovarian cancer is a combination of platinum-paclitaxel. One strategy to improve the outcome for patients is to add other agents to standard therapy. Doxil is active in relapsed disease and has a response rate of 25% in platinum-resistant relapsed disease. A dose finding study of doxil-carboplatin-paclitaxel was therefore undertaken in women receiving first-line therapy. Thirty-one women with epithelial ovarian cancer or mixed Mullerian tumours of the ovary were enrolled. The doses of carboplatin, paclitaxel and doxil were as follows: carboplatin AUC 5 and 6; paclitaxel, 135 and 175 mg m(-2); doxil 20, 30, 40 and 50 mg m(-2). Schedules examined included treatment cycles of 21 and 28 days, and an alternating schedule of carboplatin-paclitaxel (q 21) with doxil being administered every other course (q 42). The dose-limiting toxicities were found to be neutropenia, stomatitis and palmar plantar syndrome and the maximum tolerated dose was defined as; carboplatin AUC 5, paclitaxel 175 mg m(-2) and doxil 30 mg m(-2) q 21. Reducing the paclitaxel dose to 135 mg m(-2) did not allow the doxil dose to be increased. Delivering doxil on alternate cycles at doses of 40 and 50 mg m(-2) also resulted in dose-limiting toxicities. The recommended doses for phase II/III trials are carboplatin AUC 6, paclitaxel 175 mg m(-2), doxil 30 mg m(-2) q 28 or carboplatin AUC 5, paclitaxel 175 mg m(-2), doxil 20 mg m(-2) q 21. Grade 3/4 haematologic toxicity was common at the recommended phase II doses but was short lived and not clinically important and non-haematologic toxicities were generally mild and consisted of nausea, paraesthesiae, stomatitis and palmar plantar syndrome..

BACKGROUND: Granulocyte colony-stimulating factor (G-CSF) allows cycles of conventional bolus chemotherapy to be accelerated with reduction in treatment time and a boost in dose intensity. Theoretically, this approach could be hazardous with infusional 5-fluorouracil (5-FU) chemotherapy, since G-CSF-stimulated neutrophil proliferation would be occurring in the face of continuous S-phase active 5-FU. We performed this phase II randomised study to compare the safety, tolerability and efficacy of conventional 3-weekly epirubicin, cyclophosphamide and continuous infusional 5-FU (infusional ECF) to an accelerated 2-weekly schedule with G-CSF support, in patients with advanced breast cancer. PATIENTS AND METHODS: Twenty-seven patients were randomised. with 14 in the accelerated arm. Patients received bolus epirubicin 60 mg/m2 and cyclophosphamide 600 mg/m2 every 3 weeks (conventional arm) or every 2 weeks (accelerated arm) and 5-FU 200 mg/m2/day continuous infusion throughout. G-CSF 300 microg/day s.c. on days 10-12 was given each accelerated cycle. RESULTS: There were no treatment delays secondary to inadequate neutrophil or platelet recovery in either arm, with higher median day 1 neutrophil counts for each cycle in the accelerated arm compared with the conventional arm. Eighty-six per cent of the planned conventional chemotherapy cycles and 82% of the planned accelerated cycles were given. There were no major differences in toxicity between the arms, with the most common grade 3 toxicities being alopecia and stomatitis. Eight patients developed neutropenic sepsis (five in the accelerated arm and three in the conventional arm). Ten patients (77%) responded in the conventional arm and nine (64%) in the accelerated arm. CONCLUSIONS: Accelerated infusional ECF with limited G-CSF support is a feasible and well-tolerated regimen with rapid haematological recovery. A 50% increase in relative dose intensity of epirubicin and cyclophosphamide is achieved, while overall treatment time is reduced by 33%..

The growth dependence of many breast cancers on oestrogen has been exploited therapeutically by oestrogen deprivation, but almost all patients eventually develop resistance largely by unknown mechanisms. Wild-type (WT) MCF-7 cells were cultured in oestrogen-deficient medium for 90 weeks in order to establish a long-term oestrogen-deprived MCF-7 (LTED) which eventually became independent of exogenous oestrogen for growth. After 15 weeks of quiescence (LTED-Q), basal growth rate increased in parallel with increasing oestrogen sensitivity. While 10(-9)M oestradiol (E2) maximally stimulated WT growth, the hypersensitive LTED (LTED-H) were maximally growth stimulated by 10(-13)M E2. By week 50, hypersensitivity was apparently lost and the cells became oestrogen independent (LTED-I), although the pure antioestrogen ICI182780 still inhibited cell growth and reversed the inhibitory effect of 10(-9)M E2 at 10(-12) to 10(-7)M. Tamoxifen (10(-7) to 10(-6)M) had a partial agonist effect on WT, but had no stimulatory effect on LTED. Whilst LTED cells have a low progesterone receptor (PgR) expression in all phases, oestrogen receptor (ER) a expression was, on average, elevated five- and seven-fold in LTED-H and LTED-I, respectively, and serine118 was phosphorylated. ERbeta expression was up-regulated and the levels of insulin receptor substrate 1 (IRS-1) remained low throughout all phases. The levels of RIP140mRNA appeared to decrease to approximately 50% of the WT message in LTED-Q and remained constant into the hypersensitive phase. No significant changes were observed in the expression of SUG-1, TIF-1 and SMRT in LTED. The overall changes in nuclear receptor interacting proteins do not appear to be involved in the hypersensitivity. Thus, the resistance of these human breast cancer cells to oestrogen-deprivation appears to be due to acquired hypersensitivity which may be explained in part by increased levels of and phosphorylated ERalpha..

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The effect of overexpressing the antiapoptotic protein BclXL in a human ovarian carcinoma cell line has been investigated in terms of sensitivity to the 2 major drugs used to treat this disease, paclitaxel and cisplatin. Stable transfection of BclXL into CH1 cells, which are relatively sensitive to cisplatin, resulted in around 2.7-fold higher expression in comparison with empty vector controls. However, this level of overexpression did not result in significant resistance in vitro to paclitaxel or cisplatin at the 50% inhibition level, using either short-term (4-day) growth inhibition or longer term colony-forming assays. By contrast, parallel subcutaneous xenograft models of these isogenic ovarian carcinoma cells in vivo, differing only in BclXL status, showed that this low-level BclXL overexpression conferred significant resistance to both paclitaxel and cisplatin in comparison with parent, nontransfected tumours. Whereas parent non-BclXL transfected tumours were highly responsive, with the disappearance of tumours for at least 50 days post treatment, tumours overexpressing BclXL grew back after 30 and 20 days after treatment with paclitaxel and cisplatin, respectively. These differences in responsiveness to paclitaxel in vivo were not attributable to any significant changes in the delivery of drug to the tumour. These data suggest that the responsiveness of ovarian cancer to paclitaxel and cisplatin in vivo, and therefore perhaps clinically, is influenced by levels of the antiapoptotic protein BclXL. Such effects may be missed in vitro when using short-term growth inhibition or clonogenic assays..

Activating oncogenic mutations of the RAS gene are common in cancer, occurring in 30% of solid tumours in adults. Inhibitors of the enzyme farnesyl protein transferase prevent a key step in the post-translational processing of the RAS protein, and were developed initially as a therapeutic strategy to inhibit cell signalling in RAS-transformed cells. As more has been learnt about the biological effects of farnesyl transferase inhibitors on cancer cells, it has become increasingly clear that tumours without oncogenic RAS mutations may also be targets for farnesyl transferase inhibitor therapy. Encouraging results from phase I and II clinical trials have emerged, creating both enthusiasm and new challenges for the optimum clinical development of this important new class of anticancer drug..

This article reviews recent advances in the treatment of metastatic breast cancer, in particular the results of randomized controlled phase III clinical trials. These have led to the evidence-based introduction of several new drugs including aromatase inhibitors, taxanes and bisphosphonates, some of which have been shown to impact on overall survival..

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Inhibitors of the enzyme farnesyl protein transferase prevent a key step in the post-translational processing of the Ras protein, and were developed initially as a therapeutic strategy to inhibit cell signalling in ras-transformed cells. As more has been learnt about the biological effects of farnesyl transferase inhibitors (FTIs) on cancer cells, it is clear that tumours without oncogenic ras mutations such as breast cancer may also be targets for FTI therapy. This article reviews the rationale for the development of FTIs, focussing on early preclinical data in breast cancer models together with preliminary results from the first phase II study of an FTI in advanced breast cancer..

Although there have been significant improvements in the first-line treatment of ovarian cancer, the options for patients who relapse have been limited. Caelyx is a new treatment using long-circulating liposomes to target delivery of doxorubicin to the tumour. This article reviews the treatment of ovarian cancer and looks at the place of Caelyx as a new second-line treatment option..

Antitumor and pharmacodynamic studies were performed in MCF-7 human breast cancer cells and companion xenografts with the farnesyl protein transferase inhibitor, R115777, presently undergoing Phase II clinical trials, including in breast cancer. R115777 inhibited growth of MCF-7 cells in vitro with an IC(50) of 0.31 +/- 0.25 microM. Exposure of MCF-7 cells to increasing concentrations of R115777 for 24 h resulted in the inhibition of protein farnesylation, as indicated by the appearance of prelamin A at concentrations >1 microM. After continuous exposure to 2 microM R115777, prelamin A levels peaked at 2 h post drug exposure and remained high for up to 72 h. R115777 administered p.o. twice daily for 10 consecutive days to mice bearing established s.c. MCF-7 xenografts induced tumor inhibition at a dose of 25 mg/kg [percentage of treated versus control (% T/C) = 63% at day 21]. Greater inhibition was observed at doses of 50 mg/kg (% T/C at day 21 = 38%) or 100 mg/kg (% T/C at day 21 = 43%). The antitumor effect appeared to be mainly cytostatic with little evidence of tumor shrinkage to less than the starting volume. Tumor response correlated with an increase in the appearance of prelamin A, but no changes in the prenylation of lamin B, heat shock protein 40, or N-Ras were detectable. In addition, significant increases in apoptotic index and p21(WAF1/CIP1) expression were observed, concomitant with a decrease in proliferation as measured by Ki-67 staining. An increase in prelamin A was also observed in peripheral blood lymphocytes in a breast cancer patient who responded to R115777. These data show that R115777 possesses preclinical antitumor activity against human breast cancer and that the appearance of prelamin A may provide a sensitive and convenient pharmacodynamic marker of inhibition of prenylation and/or response..

Tamoxifen is one of the most effective treatments for breast cancer through its ability to antagonize estrogen-dependent growth by binding estrogen receptors (ERs) and inhibiting breast epithelial cell proliferation. However, tamoxifen has estrogenic agonist effects in other tissues such as bone and endometrium because of liganded ER-activating target genes in these different cell types. Several novel antiestrogen compounds have been developed that are also selective ER modulators (SERMs) but that have a reduced agonist profile on breast and gynecological tissues. These SERMs offer the potential for enhanced efficacy and reduced toxicity compared with tamoxifen. In advanced breast cancer clinical data exist for three first-generation SERMs (toremifene, droloxifene, idoxifene), which are related to the triphenylethylene structure of tamoxifen. In Phase II trials in a total of 263 patients resistant to tamoxifen, the median objective response rate to these SERMs was only 5% (range, 0-15%), with stable disease for > or =6 months in an additional 18% (range, 9-23%). As first-line therapy for advanced breast cancer, the median response rate was 31% (range, 20-68%) with a median time to progression of 7 months. Randomized Phase III trials for toremifene and idoxifene in more than 1500 patients showed no significant difference compared with tamoxifen. Fewer clinical data exist for the structurally distinct second- and third-generation SERMs (raloxifene, arzoxifene, EM-800, and ERA-923), although a similarly low median response rate of 6% (range, 0-14%) was seen in Phase II trials in tamoxifen-resistant patients. It remains unclear whether any clinical advantage exists for second- and third-generation SERMs over tamoxifen as first-line therapy. With the emergence of potent aromatase inhibitors (AIs) that are superior to tamoxifen, the clinical questions in advanced disease have shifted to which antiestrogen (including SERMs) may be effective following failure of AIs, and whether any merit exists for combined AI/SERM therapy. The main advantage for SERM therapy probably remains in early stage-disease (adjuvant therapy or prevention), in which the estrogenic effects on bone and reduced gynecological side effects may prove more beneficial than either tamoxifen or AI. The issue is whether the current clinical data for SERMs in advanced breast cancer are sufficiently strong to encourage that further development..

While there have been significant advances in first-line chemotherapy for advanced ovarian cancer, most patients still relapse with drug-resistant disease. For patients refractory to the two most active agents (platinum and paclitaxel), there are few salvage regimens that possess significant clinical activity together with minimal treatment-related toxicities. Caelyx is a new treatment for advanced ovarian cancer, which delivers doxorubicin encapsulated in long-circulating Stealth liposomes, resulting in a prolonged circulation and enhanced tumour targeting of the drug, together with a markedly different safety profile compared with native doxorubicin. Recent phase II clinical trials in relapsed ovarian cancer have demonstrated efficacy in patients with platinum-refractory disease (defined as progression on or relapse within 6 months of previous therapy). In those with combined platinum/paclitaxel-refractory disease, the response rate was 14.5% (95% Confidence Interval (CI): 7.8-21.4%), with many patients demonstrating a prolonged duration of response of beyond 6 months. The most frequent severe (grade 3/4) toxicity with Caelyx was palmar-plantar erythrodysesthesia (PPE), which occurred in 25% of patients and was managed by dose modification or lengthening the treatment cycle. The incidence of neutropenia and alopecia was much reduced, and the cardiac safety profile was also improved compared with equivalent cumulative anthracycline doses for native doxorubicin. In summary, the evidence of clinical efficacy in patients with platinum-refractory ovarian cancer together with an improved safety profile are all strongly supportive of a positive benefit-risk profile for Caelyx in the treatment of advanced ovarian cancer following failure of first-line platinum-based therapy.

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Locally recurrent advanced breast cancer is associated with significant morbidity and one aim of treatment is to control chest wall disease. There are no published data on the efficacy of subsequent courses of chemotherapy in this setting. We reviewed the case notes of 22 patients who developed locally recurrent breast cancer despite having received previous surgery, radiotherapy and one prior course of chemotherapy for local disease. These patients were treated with further systemic chemotherapy in an attempt to palliate their symptoms and control recurrent disease. The overall objective response rate observed with chemotherapy was 26% and a further 45% had stabilization of disease during treatment. Time to progression of disease was longest with anthracycline-based regimens; this decreased with subsequent lines of treatment. Chemotherapy was a safe and effective treatment modality in the care of women with locally recurrent breast cancer. A prospective database will now be established to collect further information on this group of patients, including their quality of life..

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To grow and metastasize, solid tumours must develop their own blood supply by neo-angiogenesis. Thalidomide inhibits the processing of mRNA encoding peptide molecules including tumour necrosis factor-alpha (TNF-alpha) and the angiogenic factor vascular endothelial growth factor (VEGF). This study investigated the use of continuous low dose Thalidomide in patients with a variety of advanced malignancies. Sixty-six patients (37 women and 29 men; median age, 48 years; range 33-62 years) with advanced measurable cancer (19 ovarian, 18 renal, 17 melanoma, 12 breast cancer) received Thalidomide 100 mg orally every night until disease progression or unacceptable toxicity was encountered. Three of 18 patients with renal cancer showed partial responses and a further three patients experienced stabilization of their disease for up to 6 months. Although no objective responses were seen in the other tumour types, there were significant improvements in patients' sleeping (P < 0.05) and maintained appetite (P < 0.05). Serum and urine concentrations of basic fibroblast growth factor (bFGF), TNF-alpha and VEGF were measured during treatment and higher levels were associated with progressive disease. Thalidomide was well tolerated: Two patients developed WHO Grade 2 peripheral neuropathy and eight patients developed WHO grade 2 lethargy. No patients developed WHO grade 3 or 4 toxicity. Further studies evaluating the use of Thalidomide at higher doses as a single agent for advanced renal cancer and in combination with biochemotherapy regimens are warranted..

Two meta-analyses have suggested that the addition of an anthracycline to platinum-based chemotherapy may improve survival in advanced ovarian cancer, and two randomised trials have demonstrated superiority of paclitaxel over cyclophosphamide in platinum combinations. A combination of platinum, anthracycline and paclitaxel would, therefore, be a reasonable experimental arm of any future randomised trial in patients with epithelial ovarian carcinoma (EOC). Patients who required chemotherapy for EOC but were ineligible for standard trials or had other gynaecological tumours that required similar platinum-based chemotherapy were considered for this pilot. The platinum/anthracycline/paclitaxel regimen (G-CAT) was given 3-weekly and consisted of doxorubicin 50 mg/m(2) or epirubicin 60 mg/m(2) intravenously (i.v.) bolus, paclitaxel 175 mg/m(2) (i.v.) over 3 h and either cisplatin 75 mg/m(2) (i.v.) or carboplatin AUC 6, with granulocyte colony-stimulating factor (G-CSF) at the neutrophil nadir. Different combinations were used in order to determine the least toxic regimen. Toxicity and response were assessed according to CTC and WHO criteria, respectively. 26 patients entered the study, 13 with EOC and 13 with other gynaecological cancers (peritoneal, fallopian tube, mixed Mullerian). Median age was 49 years (range: 27-67). 8 patients received carboplatin/doxorubicin/paclitaxel, 8 cisplatin/doxorubicin/paclitaxel and 10 carboplatin/epirubicin/paclitaxel. A total of 135 cycles of chemotherapy were delivered, with a median of 6 cycles per patient (range: 2-6). 54 (40%) cycles required G-CSF support and 17 (65%) patients required at least one dose reduction. All patients experienced grade 4 neutropenia and 13 (50%) patients developed grade 3-4 thrombocytopenia (12 of whom had received carboplatin). There were 4 (15%) patients with grade 3/4 infections but no septic deaths. Non-haematological toxicities were manageable, lethargy occurred in 75% of cisplatin-treated patients. Grade 1/2 cardiotoxicity, as assessed pre- and post-treatment by left ventricular ejection fraction, was observed in 6/13 (46%) patients who had received doxorubicin and 2/7 (29%) epirubicin-treated patients. No clinically detectable cardiac toxicity was encountered. The response rate in 25 evaluable patients was 76% (12 CR, 7 PR). Dose intensity was highest in the carboplatin/epirubicin/paclitaxel combination. G-CAT shows high activity and can be administered safely, but only very fit patients are suitable for this regimen as it is associated with considerable toxicity. Carboplatin/epirubicin/paclitaxel was the best tolerated regimen overall..

PURPOSE: Eniluracil (776C85) is an effective inactivator of dihydropyrimidine dehydrogenase that allows continuous low-dose oral fluorouracil (5-FU) to be given with predicable oral bioavailability. We have assessed this as first-line oral chemotherapy for patients with advanced/metastatic breast cancer. PATIENTS AND METHODS: Patients with histologically proven, locally advanced or metastatic breast cancer without previous chemotherapy for advanced disease were entered onto this open-label phase II study. Patients received oral 5-FU 1.0 mg/m(2) with eniluracil 10 mg/m(2), both given twice daily for the first 28 days of each 35-day cycle, continuing until disease progression or unmanageable toxicity. RESULTS: Thirty-three patients were entered, with a median age of 53 years. Sixteen partial responses were seen in twenty-nine assessable patients (55%; 95% confidence interval, 37% to 73%), including responses in four (40%) out of 10 patients who had received prior adjuvant 5-FU. Seven patients had stable disease for at least 3 months with symptom improvement. Median response duration was 14 months (range, 10 to 18+ months). Toxicity was low. There were only two episodes of drug-related grade 3 nonhematologic toxicity (diarrhea and infection), and only 6%, 3%, and 3% of patients developed granulocytopenia, thrombocytopenia, and neutropenic sepsis, respectively. Mild (grade 1/2) diarrhea occurred in 39% of patients, hand-foot syndrome in 15%, nausea in 27%, and mucositis in 18%. Toxicity-associated delay and dose reduction occurred in only 2% and 5% of courses, respectively. CONCLUSION: First-line treatment with the combination of oral 5-FU and eniluracil has high activity in patients with advanced breast cancer comparable with the most active conventional cytotoxic agents but with strikingly less toxicity..

Despite the introduction of systemic chemotherapy, inflammatory breast cancer (IBC) remains a disease with a poor prognosis. We performed this phase II study to evaluate the efficacy of infusional chemotherapy as initial treatment in patients with IBC. Fifty-four patients with newly diagnosed IBC were offered infusional chemotherapy and 34 accepted. The schedule consisted of continuous infusional ECF (bolus epirubicin and cisplatin, substituted by carboplatin or cyclophosphamide in some patients) plus continuous 5-FU, given three weekly for six cycles. Following chemotherapy patients went on to have surgery and/or radiotherapy. The chemotherapy was well tolerated and resulted in an overall response rate of 79% with 35% of patients achieving a complete clinical response. The median response duration, time to progression and overall survival were 12 months (4-89+ months), 12 months (4-89+ months) and 23 months (7-89+ months), respectively. Patients had a 5 year disease free and overall survival of 11% and 29%, respectively. Infusional ECF is well tolerated and achieves a high clinical response rate in patients with IBC, but survival results do not appear to be superior to those achieved with conventional bolus chemotherapy schedules..

BACKGROUND: Ineffective tumour antigen processing is recognised as an important cause of failure of immunotherapy in melanoma. GM-CSF may augment the cytotoxic lymphocyte response by activating antigen-presenting cells. This study evaluates a schedule combining GM-CSF with biochemotherapy. PATIENTS AND METHODS: Nineteen patients with advanced malignant melanoma received cisplatin (25 mg/m2 days 1-3). dacarbazine (220 mg/m2 days 1-3), interleukin-2 (9 MIU/m2/24 h) and interferon-alpha2b (5 MIU/m2) both days 6-10 and days 17-21, and tamoxifen 40 mg/day continuously. Subcutaneous GM-CSF was given in escalating doses to three cohorts: 1) 450 microg/m2 days 4-5 and 15-16; 2) as 1) plus 225 microg/m2 days 6-10 and 17-21; 3) 450 microg/m2 days 4-10 and 15-21. Each cycle was 28 days. RESULTS: Constitutional side effects were the major non-haematological toxicity and lymphopaenia the main haematological toxicity. Six patients responded (32%, 95% confidence interval: 13%-57%), two patients had complete remission. There was an apparent trend for increasing responses with increasing GM-CSF dose; zero of six responses in cohort 1, two of seven in cohort 2 and three of six in cohort 3 (P = 0.016). Median overall survival was 6.2 months. Increasing GM-CSF doses significantly increased serum concentrations of neopterin and TNF-alpha. CONCLUSIONS: The combination of GM-CSF with biochemotherapy is feasible and there appears to be a dose-response relationship with GM-CSF in terms of host immunological response, and possibly clinical efficacy..

BACKGROUND: In many centres surgery is used as part of a combined modality approach to the treatment of inflammatory breast cancer (IBC). Nevertheless, its value is controversial given the high risk of metastatic relapse and poor overall prognosis. We have reviewed patients with true IBC prospectively treated at the Royal Marsden Hospital in chemotherapy trials to assess further the role of surgery as part of combined modality treatment. PATIENTS AND METHODS: Fifty-four patients who had responsive or stable disease to primary chemotherapy went on to have either radiotherapy alone (n = 35) or surgery plus radiotherapy (n = 19); the decision on surgery was based partly on clinician preference and partly on clinical response. RESULTS: The 35 patients undergoing radiotherapy alone had a median progression-free survival (PFS) of 16 months and median overall survival (OS) of 35 months. Twenty-four patients (69%) have relapsed with a total of twelve (34%) relapsing locally. In comparison, the 19 patients receiving both surgery and radiotherapy had a PFS of 20 months, and a median OS of 35 months. Fifteen patients (79%) have relapsed, eight (42%) of these locally. None of these differences were statistically significant. CONCLUSIONS: These results do not suggest a clinical advantage for surgery in addition to chemotherapy and radiotherapy for patients with IBC. They support the need for a prospective randomised trial to address this question..

Third-generation aromatase inhibitors extend treatment options for postmenopausal breast cancer patients refractory to initial antioestrogen therapy. This article reviews advances and recent developments in hormonal therapy, focusing in particular on exemestane, a new class of aromatase inactivator..

Our purpose was to assess the activity of alpha-interferon (IFN-alpha), interleukin-2 (IL-2) and 5 fluorouracil (5FU) administered by protracted venous infusion (PVI) as opposed to bolus injection. 55 patients with advanced renal cell cancer were treated as follows: IL-2 and IFN-alpha according to the schedule originally described by Atzpodien, with PVI 5FU 200 mg m(-2)day(-1)during weeks 5-9. 42 patients (76%) were of moderate or poor prognosis as defined by previous studies. The response rate by intention to treat was 31% (17 of 55, three complete response, 14 partial response; 95% CI = 19-45%) and in evaluable patients (completed one cycle, n = 42), it was 40% (95% CI = 26-57%). In addition, 24% (13 of 55) patients achieved disease stabilization. The overall median survival was 11 months with a 1-year survival of 45%. The median survival for evaluable patients was 18 months with 1- and 2-year survivals of 60% and 40% respectively. The median survival of responding patients was 31 months and the three patients achieving complete response remain progression-free at 14+, 18+ and 23+ months. Evaluable patients with poor prognostic features achieved a response rate of 54% and median survival of 18 months. Toxicity was significant yet manageable with 12 patients unable to complete one cycle due to side-effects and 36% experiencing grade 3-4 toxicities. The three on-treatment deaths were considered unlikely to be due to toxicity. The schedule of IFN-alpha, IL-2 and PVI 5FU has significant activity in advanced renal cell cancer with manageable toxicity. It is of particular interest that this regimen appears to have high activity in fit patients with poor prognostic features..

This article describes the design and early results of an open-label, nonrandomized phase I/II trial of oral UFT plus leucovorin therapy in combination with bolus injections of epirubicin and cyclophosphamide in patients with advanced or metastatic breast cancer. This study was designed as a cohort dose-escalation study with the principal aims being to determine dose-limiting toxicity, overall toxicity, maximum tolerated dose, tumor response, and time to disease progression. Currently there are 22 patients randomized in the study. Overall response rate to date is 56% (66% in the locally advanced group). Based on the preliminary data, the dose-limiting toxicity appears to be neutropenia and the optimum dose of UFT for use in a phase II study appears to be 300 mg/m2..

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Human breast tumors that are initially responsive to tamoxifen (TAM) eventually relapse during treatment. Estrogen receptor (ER) expression and function are often preserved in these tumors, and clinical evidence suggests that this relapse may be related to TAM's known agonistic properties. ER can interact with the activator protein-1 (AP-1) transcription factor complex through protein-protein interactions that are independent of ER DNA binding and, in certain ER-positive cells, this may allow TAM to exert an agonist response on AP-1-regulated genes. We, therefore, assessed both AP-1 DNA binding and the known AP-1 activating enzyme, c-Jun NH2-terminal kinase (JNK), in a panel of 30 ER-positive primary human breast tumors with acquired TAM resistance, as compared to a matched panel of 27 untreated control ER-positive breast tumors and a separate control set of 14 primary tumors, which included 7 ER-positive tumors that were growth-arrested by 3 months of preoperative TAM. AP-1 DNA binding activity was measured from cryopreserved tumor extracts using a labeled oligonucleotide probe containing a consensus AP-1 response element by electrophoretic mobility shift assay. JNK was first extracted from the tumor lysates by incubation over a Sepharose-bound c-Jun(1-89) fusion protein, and its activity was then measured by chemiluminescent Western blot by detection of the phosphorylated product using a phospho-Jun(Ser-63)-specific primary antibody. The set of control ER-positive breast tumors growth arrested by TAM showed no significant difference from untreated control tumors in their AP-1 DNA binding and JNK activities. In contrast, there was a significant (P < 0.001) increase in mean AP-1 DNA binding activity for the panel of ER-positive TAM-resistant (TAM-R) tumors as compared to its matched control panel of untreated tumors. Mean JNK activity in the TAM-R tumors was also significantly higher than that found in the untreated tumors (P = 0.038). Overall, there was no significant correlation between JNK activity and AP-1 DNA binding; however, regression analysis showed that, for any given level of JNK activity, the TAM-R tumors possessed a 3.5-fold increase in AP-1 DNA binding activity as compared to the untreated tumors. These findings indicate that, when compared to untreated ER-positive primary breast tumors, TAM-R tumors demonstrate significantly increased levels of AP-1 DNA binding and JNK activity, consistent with experimental models suggesting that TAM-stimulated ER-positive tumor growth may be mediated by enhanced AP-1 transcriptional activity. These observations support the need for further evaluation of these markers in breast tumors as predictors of TAM resistance..

The interaction between cell death and cell proliferation determines the growth dynamics of all tissues. Studies are described here which relate the changes in proliferation and apoptosis that occur in human breast cancer during medical therapeutic manoeuvres. Xenograft studies strongly support the involvement of increased apoptosis as well as decreased proliferation after oestrogen withdrawal, and limited studies in clinical samples confirm the involvement of both processes. Cytotoxic chemotherapy induces increases in apoptosis within 24 h of starting treatment. However, after 3 months therapy the residual cell population shows apoptotic and proliferation indices much below pretreatment levels. Further molecular studies of this "dormant" population are important to characterise the mechanism of their resistance to drug therapy. The early changes in proliferation and apoptosis may provide useful intermediate response indices..

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This study examined whether the addition of tamoxifen to the treatment regimen of patients with advanced breast cancer being treated with the aromatase inhibitor letrozole led to any pharmacokinetic or pharmacodynamic interaction. Twelve of 17 patients completed the core period of the trial in which 2.5 mg/day letrozole was administered alone for 6 weeks and in combination with 20 mg/day tamoxifen for the subsequent 6 weeks. Patients responding to treatment continued on the combination until progression of disease or any other reason for discontinuation. Plasma levels of letrozole were measured at the end of the 6-week periods of treatment with letrozole alone and the combination and once more between 4 and 8 months on combination therapy. No further measurements were done thereafter. Hormone levels were measured at 2-week intervals throughout the core period. Marked suppression of estradiol, estrone, and estrone sulfate occurred with letrozole treatment, and this was not significantly affected by the addition of tamoxifen. However, plasma levels of letrozole were reduced by a mean 37.6% during combination therapy (P<0.0001), and this reduction persisted after 4-8 months of combination therapy. Letrozole is the first drug to be described in which this pharmacokinetic interaction occurs with tamoxifen. The mechanism is likely to be a consequence of an induction of letrozole-metabolizing enzymes by tamoxifen but was not further addressed in this study. It is possible that the antitumor efficacy of letrozole may be affected. Thus, sequential therapy may be preferable with these two drugs. It is not known whether tamoxifen interacts with other members of this class of drugs or with other drugs in combination..

Endocrine treatments for human breast cancer have been based largely upon the removal of estrogenic stimuli. The regression of tumors after estrogen deprivation has generally been characterized as being due to reduced proliferation but more recently has been recognized to also involve increased apoptosis. The aim of our experiments was to define the associated changes in certain proliferation- and cell death-related biological parameters after hormone withdrawal from estrogen-dependent MCF-7 xenografts in athymic nude mice using immunohistochemical techniques. The baseline estrogen receptor (ER) level of this MCF-7 xenograft was relatively low (average H score 23) but it was strongly Bcl-2-, PgR- and pS2-positive, indicating the functional integrity of estrogen signaling. Changes in proliferation (Ki-67), apoptosis, ER, progesterone receptor (PgR), cyclin D1, p27kip1, Bcl-2 and Bax expression were assessed during the 2 weeks after estrogen deprivation. ER levels rose markedly after estrogen ablation, whereas PgR levels fell to about 10% of baseline and pS2 levels halved. The proportion of Ki-67-positive cells was unchanged after 24 hr but by day 14 had reduced by about 80%. The normal levels of cyclin D1 also reduced after estrogen withdrawal in contrast to the rapid increase in levels of cyclin-dependent kinase inhibitor p27kip1. This latter increase appeared to occur in advance of the changes in Ki-67. The proportion of apoptotic cells increased from a mean 1.5% at baseline to 2.9% after 3 days and 4.7% after 14 days. There were reductions in both Bcl-2 and Bax staining but these appeared to be greater for Bcl-2, effectively decreasing the Bcl-2/Bax ratio. Our results provide a framework for the use of these parameters as intermediate markers in comparisons of hormonal agents for human breast cancer treatment..

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Experimental laboratory data suggest that tumour growth is a balance between apoptosis and proliferation and that suppression of drug-induced apoptosis by oncogenes such as bcl-2 may be an important cause of intrinsic chemoresistance. The aims of this study were to assess the in vivo relationship of apoptosis to proliferation and Bcl-2 protein in human breast tumours both prior to chemotherapy and in the residual resistant cell population at the completion of treatment. We examined apoptotic index (AI), Ki67 and Bcl-2 protein expression in the tissue of 40 patients with operable breast cancer immediately before ECF preoperative chemotherapy, and in 20 of these patients with residual tumour, at the completion of treatment. There was a significant positive association between AI and Ki67 both before and after chemotherapy, and in their percentage change with treatment. In the residual specimens AI and Ki67 were significantly reduced compared with pre-treatment biopsies, while Bcl-2 expression showed a significant increase. No differences were seen in the pre-treatment levels of any of the variables measured between patients obtaining pathological complete response and those who did not, although numbers were small. These data suggest that apoptosis and proliferation are closely related in vivo. It is possible that the phenotype of reduced apoptosis and proliferation, and increased Bcl-2 may be associated with breast cancer cells resistant to cytotoxic chemotherapy, although this can only be proven by assessing larger numbers of patients in relation to pathological response..

The purpose of this study was to evaluate in a randomized phase II trial the efficacy and toxicity of combination biochemotherapy compared with chemotherapy alone in patients with metastatic melanoma. Sixty-five patients with metastatic melanoma (ECOG performance status 0 or 1) were randomized to receive intravenous BCNU 100 mg m(-2) (day 1, alternate courses), cisplatin 25 mg m(-2) (days 1-3), DTIC 220 mg m(-2) (days 1-3) and oral tamoxifen 40 mg (BCDT regimen) with (n = 35) or without (n = 30) subcutaneous interleukin 2 (IL-2) 18 x 10(6) iu t.d.s. (day - 2), 9 x 10(6) iu b.d. (day - 1 and 0) and interferon 2 alpha (IFN-alpha) 9 MU (days 1-3). Evidence for immune activation was determined by flow cytometric analysis of peripheral blood lymphocytes. Treatment was repeated every 4 weeks up to six courses depending on response. The overall response rate of BCDT with IL-2/IFN-alpha was 23% [95% confidence interval (CI) 10-40%] with one complete response (CR) and seven partial responses (PR), and for BCDT alone 27% (95% CI 12-46%) with eight PRs; the median durations of response were 2.8 months and 2.5 months respectively. Sites of response were similar in both groups. There was no difference between the two groups in progression-free survival or overall survival (median survival 5 months for BCDT with IL-2/IFNalpha and 5.5 months for BCDT alone). Although 3 days of subcutaneous IL-2 resulted in significant lymphopenia, evidence of immune activation was indicated by a significant rise in the percentage of CD56- (NK cells) and CD3/HLA-DR-positive (activated T cells) subsets, without any change in the percentage of CD4 or CD4 T-cell subsets. Toxicity assessment revealed a significantly higher incidence of severe thrombocytopenia in patients treated with combination chemotherapy than with chemotherapy alone (37% vs 13%, P = 0.03) and a higher incidence of grade 3/4 flu-like symptoms (20% vs 10%) and fatigue (26% vs 13%). The addition of subcutaneous IL-2 and IFNalpha to BCDT chemotherapy in a randomized phase II trial resulted in immune activation but did not improve response rates in patients with metastatic melanoma, and indeed may increase some treatment-related toxicity..

PURPOSE: We previously developed an inpatient regimen that consisted of infusional fluorouracil (5-FU), epirubicin, and cisplatin (ECisF), with a response rate of 86% in advanced breast cancer. The current phase II 2:1 randomized study investigated whether cyclophosphamide can be substituted for cisplatin (ECycloF) to reduce toxicity and allow the regimen to be administered on an outpatient basis without loss of efficacy. PATIENTS AND METHODS: Ninety-six women (median age, 49 years; range, 28 to 73) with breast cancer (59 metastatic, 37 locally advanced) received continuous infusional 5-FU (200 mg/m2/d via Hickman line) and six cycles of epirubicin (60 mg/m2 every 21 days) with either cyclophosphamide 600 mg/m2 every 21 days (38 metastatic, 24 locally advanced) or cisplatin 60 mg/m2 every 21 days (21 metastatic, 13 locally advanced). There were no significant differences in patient characteristics between these groups. RESULTS: ECycloF was better tolerated than ECisF in terms of lethargy (P = .005), stomatitis (P = .008), plantar palmar erythema (P = .02), constipation (P < .001), thrombosis (P = .0014), and nausea and vomiting (P = .05). Although there was a trend toward more anemia and leukopenia with ECisF (P =. 1), there was no significant difference in the rates of infection. Efficacy was comparable in terms of overall response (69% v 68%), complete response (CR; 13% v 15%), and median progression-free survival (9 v 8 months). CONCLUSION: ECycloF is an outpatient regimen with a lower incidence of severe nonhematologic toxicity than inpatient ECisF; it has comparable efficacy and is considerably more economical..

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Preliminary studies have suggested that measuring the ability of immunoreactive 67-kDa estrogen receptor (ER) to bind DNA and form in vitro complexes with its cognate estrogen response element (ERE) might serve to identify breast tumors most likely to respond to antiestrogens like tamoxifen. Data from two different surveys of untreated primary breast tumors confirmed that only 67% (74 of 111) of ER-positive tumors express a receptor capable of forming ER-ERE complexes by gel-shift assay, with tumors of lower ER content having significantly reduced ER DNA-binding frequency (56%) relative to those of higher ER content (82%; P = 0.007). In contrast to these untreated tumors, a panel of 41 receptor-positive breast tumors excised after acquiring clinical resistance to tamoxifen during either primary (n = 26) or adjuvant therapy (n = 15) showed a significantly greater ER DNA-binding frequency, with nearly 90% capable of forming ER-ERE complexes (P < 0.02). To assess experimentally whether ER DNA-binding function is altered during the development of antiestrogen resistance, nude mouse MCF-7 tumor xenografts were analyzed before and after the acquisition of in vivo resistance to either tamoxifen or a pure steroidal antiestrogen, ICI 182,780. Tamoxifen-resistant MCF-7 tumors retained full expression of 67-kDa DNA-binding ER, and despite a markedly reduced ER content in the ICI 182,780-treated tumors, the expressed ER in these antiestrogen-resistant tumors exhibited full ability to form ER-ERE complexes. These findings indicate that breast tumors with acquired antiestrogen resistance continue to express ER of normal size and DNA-binding ability and suggest that the failure of antiestrogens to arrest tumor growth during emergence of clinical resistance results from an altered gene-regulatory mechanism(s) other than ER-ERE complex formation..

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Hormonal breast cancer therapies have traditionally been considered cytostatic, but recent pre-clinical data suggest that anti-oestrogens can induce apoptosis. The aim of this study was to assess whether tamoxifen (TAM) and ICI 182780 (ICI) could induce apoptosis in human breast cancer, and whether this was related to oestrogen receptor status. We measured apoptosis in primary breast cancer patients before and after pre-surgical treatment with 20 mg/day TAM (study 1) or 6 or 18 mg/day ICI (study 2). In each study there was a randomised non-treatment (NT) control group. TAM significantly increased apoptotic index (AI) in ER+ but not in ER- tumours. There was a significant increase in AI following treatment with ICI. Insufficient pairs of samples were available to determine whether this change was confined to ER+ tumours, but in a cross-sectional analysis AI was significantly higher in excision biopsies for ICI-treated than NT patients for ER+ but not ER- tumours. Our results provide clinical evidence that apoptosis may be induced in ER+ primary breast cancer by both non-steroidal and steroidal anti-oestrogens..

Oestrogen receptor (ER) status is the only biochemical predictive factor which is routinely measured in breast carcinomas. ER gene mutations can profoundly change the biochemical activity of the protein. If these occurred in vivo, they could be expected to affect breast cancer risk or phenotype, such as endocrine responsiveness. However, no mutations of significance have been described in breast carcinomas. In contrast, numerous variant forms of ER have been reported at the mRNA level. Most of these appear to be due to aberrant exon splicing which results in predicted protein products whose activities range from dominant positive to dominant negative. In some instances, these mRNA variants have also been demonstrated in normal tissue (breast and others). Their biological and clinical significance might be profound, but remain to be established because of a lack of evidence for their existence at the protein level. On the currently available data, routine analysis for ER mutants and variants is not justified..

A strong HLA association is seen in coeliac disease [specifically to the DQ(alpha1*0501,beta1*0201 heterodimer], but this cannot entirely account for the increased risk seen in relatives of affected cases. One or more genes at HLA-unlinked loci also predispose to coeliac disease and are probably stronger determinants of disease susceptibility than HLA. A recent study has proposed a number of candidate regions on chromosomes 6p23 (distinct from HLA), 6p12, 3q27, 5q33.3, 7q31.3, 11p11, 15q26, 19p13.3, 19q13.1, 19q13.4 and 22cen for the location of a non-HLA linked susceptibility gene. We have examined these regions in 28 coeliac disease families by linkage analysis. There was excess sharing of chromosome 6p markers, but no support for a predisposition locus telomeric to HLA. No significant evidence in favour of linkage to coeliac disease was obtained for chromosomes 3q27, 5q33.3, 7q31.3, 11p11, 19p13.3, 19q13.1, 19q13.4 or 22cen. There was, however, excess sharing close to D15S642. The maximum non-parametric linkage score was 1.99 (P = 0.03). Although the evidence for linkage of coeliac disease to chromosome 15q26 is not strong, the well established association between coeliac disease and insulin dependent diabetes mellitus, together with the mapping of an IDDM susceptibility locus (IDDM3) to chromosome 15q26, provide indirect support for this as a candidate locus conferring susceptibility to coeliac disease in some families..

Expression of epidermal growth factor receptor (EGFR) or of c-erbB2 in primary breast cancer has been shown to predict for a poor chance of subsequent response of recurrent/metastatic disease to endocrine therapy. To assess the role of these receptors in the development of tamoxifen resistance, we examined their expression immunohistochemically on paraffin-embedded sections from breast cancers from 155 patients whose disease was progressing on tamoxifen therapy. Patients were categorized into those who initially responded to therapy (n = 56), those who never responded (n = 39), and those who relapsed while on adjuvant therapy and may or may not have "responded" (n = 60). In 61 cases, pretreatment specimens were also obtained for direct comparison with the resistance specimen for each patient. None of the 18 pretreatment samples from patients who responded to therapy expressed c-erbB2, and 1 of 18 expressed EGFR. Of the nonresponders, 7 of 18 expressed EGFR pretreatment, and 4 of 18 expressed c-erbB2 (1 patient expressed both receptors). Results confirmed previous findings that when considered independently, expression of either receptor pretreatment tended to predict for a poor chance of response (EGFR, P = 0.046; c-erbB2, P = 0.11). Importantly, patients who were either EGFR positive and/or c-erbB2 positive had a much poorer chance of response than "double negatives" (response rates of 1 of 11 and 17 of 25, respectively; P = 0.0039). At the time of disease progression compared to pretreatment, there was no significant change in expression of either receptor, irrespective of initial response. The inverse relationship between EGFR and estrogen receptor was maintained at relapse on tamoxifen. These data argue strongly against the acquired expression of these receptors during treatment playing a major role in the development of tamoxifen resistance in human breast cancer..

The widespread use of the antiestrogen tamoxifen in the management of breast cancer has resulted in more patients eventually developing acquired resistance to the drug. Tumors may often retain sensitivity to further endocrine therapies despite resistance to tamoxifen. The basis for this partial form of acquired resistance in vivo has been the subject of several recent investigations and the likely mechanisms are reviewed in this article. Ineffective antiestrogen blockade could result from metabolic tolerance and inadequate intra-tumoral concentrations of the drug. Alternatively, there is experimental evidence that tamoxifen's partial agonist activity may be responsible for stimulation of tumor re-growth. Studies of the estrogen receptor (ER) have shown that in many cases expression of a fully functional wild-type receptor continues at relapse. Experimental evidence that mutant or variant forms of the receptor may account for resistance have not been confirmed by recent in vivo studies. There is some evidence for re-modeling of ER expression at relapse and it remains to be determined if there is enhanced sensitivity of ER+ cells to hormonal stimuli at relapse. Clonal selection of an ER- phenotype may occur in some instances, especially in patients with ER+ breast cancer who fail on adjuvant tamoxifen with relapse at distant sites. Finally, there is an increased understanding of the molecular pathways which regulate cell growth and apoptosis in hormone-sensitive cells and constitutive activation of these may provide the cell with a mechanism to bypass the requirement for estrogens. These advances in tumor biology have been matched by the clinical development of novel antiestrogens with less agonist activity and several clinical trials are ongoing to see if these new agents can delay the onset of acquired antiestrogen resistance..

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Changes in estrogen receptor (ER) expression and function may explain the development of tamoxifen resistance in breast cancer. ER expression was measured by an immunohistochemical assay, validated for use in tamoxifen-treated tumors against a biochemical enzyme immunoassay, in 72 paired biopsies taken before treatment and at progression or relapse on tamoxifen. Progesterone receptor (PgR) and pS2 gene expression were also measured immunohistochemically as an indicator of ER function. Overall the frequency of ER expression was reduced from 37 of 72 (51%) pretamoxifen to 21 of 72 (29%) at progression or relapse, with a significant reduction in the quantitative level of ER (P < 0.0001; Wilcoxon signed rank sum test). Tumors treated with primary tamoxifen that responded but then developed acquired resistance frequently remained ER positive (ER+) at relapse: 16 of 18 (89%) were ER+ pretamoxifen (75% of these expressed either PgR or pS2) and 11 of 18 (61%) were ER+ at relapse (82% continued to express PgR or pS2). In contrast, only 3 of 20 (15%) tumors that progressed on primary tamoxifen with de novo resistance were ER+ pretamoxifen, and all tumors were ER- at progression. At progression, 6 of 20 (30%) of these tumors expressed high levels of PgR (mean H-score, 98) and/or pS2 (mean, 50% cells positive), despite being ER-. In tumors that recurred during adjuvant tamoxifen therapy, including locoregional and metastatic lesions, ER expression was significantly reduced from 18 of 34 (53%) in the original primary tumor to 10 of 34 (29%) at relapse (P = 0.002). PgR expression was likewise significantly reduced in this group (P = 0.001). This study confirms that expression of a functional ER in breast cancer is a strong predictor for primary response to tamoxifen. Although ER was reduced in tamoxifen-resistant tumors overall, the development of acquired resistance was associated with maintained ER expression and function in many tumors, whereas de novo resistance remained related to lack of ER expression. Recurrence during adjuvant tamoxifen was associated with development of an ER/PgR-negative phenotype in some tumors. These data imply that separate mechanisms of resistance may occur in these different clinical subgroups..

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PURPOSE: To investigate the efficacy of continuous infusion fluorouracil (5FU) with every-3-week epirubicin and cisplatin (ECF) as primary chemotherapy instead of immediate mastectomy for patients with large, potentially operable, breast cancer. PATIENTS AND METHODS: Fifty patients with large operable breast cancer, median tumor diameter 6 cm (range, 3 to 12), were treated with 5FU 200 mg/m2/d via a Hickman line using an ambulatory pump for 6 months with epirubicin 50 mg/m2 intravenously (IV) and cisplatin 60 mg/m2 IV every 3 weeks for eight courses. Subsequent surgery and/or radiotherapy was determined by clinical response. RESULTS: Forty-nine patients achieved an overall response (98%; 95% confidence interval [CI], 94% to 100%), including 33 complete clinical remissions (CRs) (66%; 95% CI, 53% to 79%). Only three patients (6%) still required mastectomy. Tumor cellularity was markedly reduced on repeat needle biopsy following 3 weeks of treatment in 81% of patients versus only 36% in similar patients after conventional chemotherapy (P < .002). Severe (World Health Organization [WHO] grade 3 to 4) toxicity was rare, with nausea/vomiting being the most common, occurring in 20% of patients. CONCLUSION: Primary infusional ECF appears to be more active on clinical and histopathologic grounds than conventional chemotherapy for large operable breast cancer and is well tolerated. This approach now merits randomized comparison to determine if high CR rates may translate into improved survival..

Thirteen postmenopausal women with advanced breast cancer were enrolled in an open randomized Phase I trial of a new p.o. active aromatase inhibitor, CGS 20267 (letrozole). The primary aim of the trial was to assess the impact of two doses of letrozole (0.5 and 2. 5 mg/day) on the peripheral aromatization of androstenedione to estrone. An in vivo isotopic technique was used to measure peripheral aromatization in each patient before treatment. The patients were then randomly assigned to one of the two doses, and measurements of aromatization were repeated after 6 weeks. At 0.5 mg and 2.5 mg/day, letrozole inhibited aromatization by 98.4% (97.3 to >99.1) and >98.9% (98.5 to >99.1; geometric means and ranges), respectively. Plasma estrogen levels were also measured before and during treatment. At the dose of 0.5 mg/day estrone and estradiol levels fell by 82.0% and 84.1% (geometric means), respectively. At the dose of 2.5 mg/ day, the estrogens fell by 80.8% and 68.1%, respectively. There were no significant differences between the doses in aromatase inhibition. No formal statistical analysis was performed on the estrogen data. Letrozole is therefore a highly effective inhibitor of aromatase, causing near complete inhibition of the enzyme in peripheral tissues at the doses investigated. The falls in estrogen levels were greater than those seen with earlier generation aromatase inhibitors..

The exon 5 deletion splice variant of estrogen receptor (delta 5 ER), which in vitro is constitutively active in the absence of estrogens, may have a role in conferring both tamoxifen resistance and ER-related phenotype in breast cancer. We have investigated the expression of this variant in vivo (at the level of mRNA) in relation to known tamoxifen resistance and expression of the estrogen-regulated genes progesterone receptor (PgR) and pS2. The amount of delta 5 ER mRNA relative to wild type (WT) ER mRNA (% delta 5/WT) was assayed in 70 tamoxifen-resistant and 50 primary breast carcinomas using reverse transcription/PCR. Both WT and delta 5 ER mRNA were detected in the majority of tumors, although delta 5 ER was detected only in the presence of WT ER. Overall no significant difference was seen in % delta 5/WT ER between tamoxifen-resistant and primary control tumors (medians, 13 and 15%, respectively). Tumors in both control and resistant groups which expressed PgR/pS2 in the absence of measurable ER protein (ER- PgR+ and ER- pS2+) had significantly higher delta 5 ER mRNA levels compared with other phenotypes (P < 0.002). This association with ER-/pS2+ tumors has not been demonstrated previously. In ER+ tumors which expressed pS2, significantly greater delta 5 ER mRNA expression was observed in tamoxifen-resistant compared with control tumors (P = 0.05). A similar although nonsignificant trend was observed in ER+ PgR+ tumors. While delta 5 ER mRNA is unlikely to be responsible for tamoxifen resistance in most breast cancers, elevated delta 5 ER mRNA levels may be important in some tumors, especially those which continue to express high levels of PgR/pS2..

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AIM: To validate the use of a new mouse monoclonal antibody (1D5) directed against the N-terminal domain (A/B region) of the oestrogen receptor in an immunohistochemical assay (ER-IHA) for paraffin wax embedded tissue. METHODS: Breast cancer specimens were surgically obtained from 119 previously untreated patients. For comparison, oestrogen receptor was measured from cytosol fractions using an established oestrogen receptor enzyme immunoassay (ER-EIA) method. Oestrogen receptor "H-scores" were obtained from the ER-IHA after antigen retrieval using microwave treatment. Where discrepancies occurred between the two methods, further immunohistochemistry was performed using the H222 antibody from the Abbott Laboratories ER-ICA kit. RESULTS: The correlation between the two methods was non- linear, but despite this there was an 86% concordance between ER-EIA and ER-IHA using the 1D5 ER antibody. Fifty four per cent of tumours (64/119) were oestrogen receptor positive and 32% (38/119) were negative by both assays. A mismatch between the ER-EIA and ER-IHA occurred in 17 cases. Seven tumours were IHA positive but EIA+, but five of these were borderline negative by EIA, having values of > 5 and < 10 fmol/mg protein. Ten tumours were IHA negative and EIA+; four of these tumours were completely negative by IHA in the section studied. A further IHA assay, carried out on the 17 tumour mismatches with H222 antibody, showed that three tumours remained substantially discordant. These three tumours were strongly positive with the 1D5 antibody and negative with the H222 antibody. Two of these discordant tumours were of the rare ER negative and PgR positive phenotype and may contain oestrogen receptor that is of biological interest but which lacks the hormone binding epitope. CONCLUSIONS: The concordance between the classic enzyme immunoassay technique and the new immunohistochemical method on paraffin wax embedded sections was good. Moreover, the IHA technique using the 1D5 antibody against the N-terminal was easily reproducible. This technique may allow oestrogen receptor content to be determined in large cohorts of patients in whom archival tumour material is available..

Using reverse transcription (RT)/PCR we have shown that four breast cancer cell lines expressed oestrogen receptor (ER) mRNA, irrespective of whether they were assessed as ER-positive (MCF-7 and BT-474) or ER-negative (MDA-MB-231 and BT-20) by enzyme immunoassay (EIA). In addition to the wild type (WT) form, they were all found to express the exon 5-deleted variant (V) form of ER mRNA by RT/PCR; this is thought to code for a truncated constitutively active protein. By Northern blot analysis only the ER-positive cell lines (MCF-7 and BT-474) were found to express detectable levels of ER mRNA. Oestradiol-induced growth was found only in the ER-positive (by EIA) cell lines. These results confirm that the differences between ER-positive and ER-negative cell lines are quantitative rather than qualitative. As low levels of ER mRNA could be detected by RT/PCR, this may reflect the greater sensitivity of this approach. The presence of exon 5-deleted V form ER mRNA in addition to the WT form in all four breast cancer cell lines may allow these lines to be used to assess differential regulation of transcription and the impact of this on their oestrogen dependence..

Vorozole is an orally active, nonsteroidal aromatase inhibitor. Twenty-four postmenopausal patients with advanced breast cancer who had relapsed after treatment with tamoxifen received three separate daily doses of vorozole (1, 2.5, and 5 mg) each for 1 month in a randomized, double-blind, phase II study. There was significant suppression (P < 0.001) of serum estradiol at all three doses (median reduction, 91, 90, and 89%, respectively). There was a significant trend (P = 0.02) for estradiol to be suppressed below the detection limit of the assay (3 pmol/liter) more frequently with an increasing dose of vorozole; 13, 31, and 40% respectively. Estrone and estrone-sulfate levels were likewise reduced at each dose by 52-55% and 64-69%, respectively. There was no significant effect at any dose on aldosterone, testosterone, androstenedione, 17 alpha-hydroxyprogesterone, or thyroid-stimulating hormone levels. A small reduction in cortisol was seen at the 5 mg dose, although the relevance is unclear given that 17 alpha-hydroxyprogesterone levels did not rise. Eight patients (33%) achieved an objective response (2 complete remission, 6 partial remission) with a median response duration of 13 months. Four patients (17%) achieved disease stabilization for more than 6 months. Patients who had responded previously to tamoxifen were more likely to respond to vorozole. There were no significant clinical side effects and the drug was well tolerated. These data suggest that vorozole is a potent and selective oral aromatase inhibitor for use in postmenopausal breast cancer..

The expression of the bcl-2 proto-oncogene, which is associated with prolonged cell survival and prevention of programmed cell death, was investigated in human primary breast carcinomas prior to and following endocrine therapy with the anti-oestrogen, tamoxifen. Using the BCL-2-100 antibody, a 26-kD protein was detected by western immunoblot in the cytosols of oestrogen receptor (ER)+ve human breast cancers. In a cross-sectional study, the immunohistochemical expression of Bcl-2 was observed in 32% of invasive breast cancers, but in 65% of tumours treated with tamoxifen (P = 0.009). There was a significant association of Bcl-2 with ER status, with 64% of untreated and 88% of tamoxifen-treated Bcl-2-positive tumours being ER+ve. A significantly lower Ki-67 score was found in tamoxifen-treated tumours which were Bcl-2-positive compared with Bcl-2-negative (9.3 versus 24.6%, P = 0.01). In a separate series of sequential Trucut biopsies from 18 patients, the frequency of Bcl-2 expression was increased in ER+ve tumours from 3/12 to 8/11 following tamoxifen (P = 0.04). This was also associated with a significant reduction in mean Ki-67 score from 32 to 12% (P = 0.0004). The observations from this study clearly indicate that Bcl-2 in human breast cancer is associated with ER status, and that expression is enhanced in ER+ve tumours following tamoxifen, in association with reduced cell proliferation..

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Breast cancer patients who acquire tamoxifen resistance may respond to second-line hormonal therapy or progress to true endocrine resistance. The biological basis for these processes are poorly understood. Following successful therapy with tamoxifen there is little evidence at relapse for change in either the host endocrine environment or drug metabolic profile to account for the development of acquired resistance. Many tamoxifen resistant tumours still retain a structurally and functionally normal oestrogen receptor (ER) and yet will grow independent of oestrogen. The oestrogen-regulated molecular events which normally govern the growth of hormone-sensitive breast cancer involve a complex autocrine and paracrine interaction between several peptide growth factors (including TGF alpha, IGF-1 and TGF beta), their receptors and signal transduction pathways. Evidence now exists that constitutive activity of many of these mediators of the mitogenic signal can bypass the cell's dependence on oestrogen and provide a mechanism for hormone-independent growth. Research into these molecular mechanisms may result in a better understanding of how to overcome the clinical problem of tamoxifen resistance..