.tmb-propic-md.jpg?Culture=en&sfvrsn=c25d2b2f_9 "Professor Louis Chesler (Profile pic)")
Thousands of men with prostate cancer in England will be offered a more precise form of radiotherapy that cuts treatment time by up to 75 per cent, based on the results of a trial led by The Institute of Cancer Research, London and The Royal Marsden NHS Foundation Trust.
The PACE-B trial showed that stereotactic body radiotherapy (SBRT) – also known as stereotactic ablative radiotherapy (SABR) – which is more powerful and targeted than standard external radiotherapy, can effectively treat many small, low-risk prostate cancers in just five hospital visits, rather than 20.
Now, all 48 NHS radiotherapy centres in England will begin offering this five-session SBRT treatment to eligible men within the next three months.
Who is SABR for?
NHS England has approved SBRT for men in England with early-stage prostate cancer that hasn’t grown outside the prostate, and that has a low or medium risk of growing or spreading.
NHS England’s modelling suggests that around 3,500 men with this type of early-stage low or medium-risk prostate cancer will choose the new treatment over standard radiotherapy each year.
Power and precision
SBRT combines the power of multiple tiny, intense energy beams aimed at a tumour from different angles. These beams converge over the tumour, delivering a very high dose of radiation to cancer cells while minimising the impact on healthy cells.
Because of its pinpoint accuracy, SBRT is especially suitable for treating small, well-defined cancers. If a cancer has begun to grow or spread, standard radiotherapy is usually a better option, as its wider beams can kill cancer cells outside the tumour.
The PACE-B trial, which was managed by the Clinical Trials and Statistics Unit at the ICR, tested whether five sessions of SBRT radiotherapy in a fortnight are as effective for treating low-risk, localised prostate cancer as 20 sessions of standard intensity-modulated radiotherapy (IMRT) delivered Monday to Friday for four weeks.
The phase III international randomised trial found that both treatments worked equally well, keeping cancer under control in moth patients.
Keeping cancer under control
Five years after entering the study, cancer remained under control, with no recurrence or worsening, in 96 per cent of patients who had SBRT compared to 95 per cent of patients who had conventional radiation.
Side effects were low in both groups. At five years post-treatment, 5.5 per cent of patients who received SBRT experienced grade 2 or higher side effects affecting the genital or urinary organs, compared to 3.2 per cent in the conventional group. Only one person in each group experienced grade 2 or higher gastrointestinal side effects. Grade 2 side effects can be bothersome, and may affect daily activity, but they require little to no medical treatment.
Because it only takes a quarter of the sessions required for standard radiotherapy, SBRT puts much less strain on people and the health service. If, as NHS England estimates, 1 in 5 eligible men choose it over standard radiotherapy, an extra 50,000 prostate cancer treatment appointments could be made available each year.
'A game-changer'
Professor Emma Hall, Director of the Clinical Trials and Statistics Unit at The Institute of Cancer Research, London, which managed the PACE-B trial, said:
“I am delighted to see that SBRT, offering patients treatment in just five doses rather than 20, is now being recommended by the NHS. Treating patients in a fraction of the time is a game-changer – they can spend less time in hospital and travelling to appointments, whilst still receiving highly effective treatment.”
Professor Nicholas van As, Consultant Clinical Oncologist at The Royal Marsden NHS Foundation Trust, Professor in Precision Prostate Radiotherapy at The Institute of Cancer Research, London, and Chief Investigator of the PACE-B trial, said:
“We are delighted that eligible prostate cancer patients across England will now be able to benefit from this treatment following NHS England's announcement.
“The news demonstrates the value of clinical research in improving cancer care. At The Royal Marsden and the ICR, we are focused on developing smarter, better and kinder treatments for patients across the UK and around the world.
“The PACE-B trial was designed to answer an important question: can we safely deliver prostate radiotherapy in far fewer treatment sessions without compromising outcomes? The results showed that we can. Delivering treatment in just five sessions was as safe and effective as conventional radiotherapy, while significantly reducing the burden of treatment for patients. The findings helped establish the evidence base for wider adoption of the treatment and have informed clinical practice internationally.”
Professor Peter Johnson, NHS National Clinical Director for Cancer, said:
“This technology lets us focus a powerful and precise beam of radiotherapy directly onto the cancer, limiting the damage to healthy cells. And the fact it can be delivered in 15 fewer doses will help men get back to living their lives far more quickly.”
Banner image: IMRT radiotherapy machine. SBRT can be delivered on a Cyberknife or standard radiotherapy machines.
