Urinary and sexual side effects less likely after advanced radiotherapy than surgery for advanced prostate cancer patients

Men with prostate cancer are less likely to experience urinary and sexual side effects two years after treatment with an advanced type of radiotherapy than surgery, according to researchers from The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research, London.

The PACE-A study is the world’s first randomised trial to compare the long-term side effects of stereotactic body radiotherapy (SBRT) versus surgery in patients with early-stage prostate cancer. Results from the trial are being presented at the 2023 ASCO Genitourinary Cancers Symposium today.

123 men from 10 UK centres were enrolled in the trial, with 59 ultimately treated with SBRT and 50 with surgery. After two years, significantly fewer patients (4.5 per cent) treated with SBRT reported needing to use urinary pads, which manage urinary incontinence, compared with surgery (47 per cent). Patients treated with SBRT also reported better sexual function after two years than those treated with surgery.

However, although moderate or serious bowel problems were not reported by many men in the study, those treated with SBRT were more likely (16 per cent) than surgical patients to report minor problems (0 per cent).

Sub-millimetre precision

SBRT, which can be carried out on a CyberKnife or a modern linear accelerator, allows clinicians to target tumours to sub-millimetre precision. It delivers five high doses of radiation to patients over one to two weeks, compared with standard radiotherapy, which delivers more moderate doses through approximately 20 sessions over four weeks. The Royal Marsden has two Cyberknife machines, which were funded by The Royal Marsden Cancer Charity.

Chief Investigator Professor Nicholas van As, Medical Director and Consultant Clinical Oncologist at The Royal Marsden NHS Foundation Trust, and Professor in Precision Prostate Radiotherapy at The Institute of Cancer Research, London, said: 

“This world-first study reveals that SBRT, an advanced form of radiotherapy now widely available across the UK, is often kinder and can mean less long-term side effects than surgery for prostate cancer patients. 

“One of the biggest concerns for men I see in clinic ahead of treatment for prostate cancer is whether it will make them incontinent, and many worry about the impact on their sexual function too. While there is a risk both SBRT and surgery will cause problems, these results suggest SBRT is less likely to.

“Going forwards, these results should support clinicians in facilitating important discussions with prostate cancer patients about whether to opt for SBRT or surgery, helping them make an informed decision based on their individual needs and concerns.” 

Patient experience

Professor Emma Hall, Co-Director of the Clinical Trials and Statistics Unit at The Institute of Cancer Research, London which is managing the PACE trial said:

“Understanding how cancer treatments affect patients’ lives should be at the heart of research. This important trial uses patient-reported outcomes to understand how various treatments for prostate cancer affect patients following recovery.

“It’s great to see that using SBRT for early-stage prostate cancer can help people avoid sexual and urinary side effects that are commonly associated with surgery, and I hope these findings will help men decide, with their clinician, the best course of treatment for them.”

'Side effects have been minimal'

Alexander Szczerbiuk, 73 from Morden, was diagnosed with prostate cancer in November 2017 at his local hospital following a blood test which revealed his prostate-specific antigen (PSA) levels were raised. Alexander was referred to The Royal Marsden and, after being recruited to the PACE-A trial, was treated with SBRT via CyberKnife. He said:

“In terms of treatment, you couldn’t wish for anything better. It was only two months from my diagnosis to the last of my five CyberKnife sessions, and I was pleased as punch everything happened so quickly.

“Before the treatment, my biggest concern was incontinence, as I really couldn’t bear the thought of having to use urinary pads. This meant I was delighted to be selected for CyberKnife which, as a minimally invasive option, was a no-brainer. Fortunately, the side effects have been minimal and, while I experience rectal bleeding very occasionally, I urinate normally and have never needed to use a pad."

The PACE-A trial was funded by Accuray and Varian, a Siemens Healthineers company, sponsored by The Royal Marsden, and managed by the Clinical Trials and Statistics Unit at The Institute of Cancer Research (ICR).