Advanced radiotherapy could cure nearly three in four cases of terminal prostate cancer.
Researchers said 71 per cent of men with the disease were free of it five years after treatment.
They believe the technique could benefit thousands of patients every year if it was available on the NHS.
Developed in London, the extremely precise form of radiotherapy is called intensity-modulated radiation therapy or IMRT. It lets specialists blast the lymph nodes in the pelvis, often the first place advanced cancer reaches after leaving the prostate.
Conventional therapy has been judged too dangerous because of the impact on the bladder, which sits nearby. IMRT allows the radiation to be fired in a far more precise pattern, sparing the rest of the body.
Researchers said 71 per cent of men with terminal prostate cancer were free of it five years after treatment (stock photo)
It is quick – taking only two minutes a time for 20 days, compared with the previous 45 minutes a session for 37 days.
The trial of 447 men at The Royal Marsden in London found that only 8 to 16 per cent of patients had bladder or bowel problems five years after receiving the two-week course.
It also produced half the chance of suffering side effects to the bladder and bowel associated with conventional radiotherapy.
The trial, which was funded by Cancer Research UK, saw only 13 per cent of patients die within five years, and some of these died from other causes, with only 8 per cent killed by prostate cancer itself.
The 71 per cent disease-free figure is remarkable, considering the patients were thought to have had terminal, incurable cancer.
Although there is a chance the cancer could return, the five-year landmark is considered a cure. David Dearnaley, who led the study at the Institute of Cancer Research in London, said: ‘Our trial was one of the first of this revolutionary radiotherapy technique, which was pioneered by colleagues here at the ICR and The Royal Marsden.
The advanced radiotherapy treatment is quick – taking only two minutes a time for 20 days, compared with the previous 45 minutes a session for 37 days (stock photo)
‘These long-term results demonstrate that using IMRT to target the pelvic lymph nodes is safe and effective for men with prostate cancer.’
The professor said it could help an extra 3,000 patients a year.
‘This technique has already proven to be a game changer for men with prostate cancer,’ he added. ‘I’m excited to see this treatment become available to every man with prostate cancer who could benefit from it.
‘Between treating the first ever patients on this trial, and those we treat today, there has been a complete revolution.
‘When we first started it took 45 minutes to provide treatment; today it only takes two or three minutes. It’s been a giant leap forward for radiotherapy treatment.’ He is about to start a much larger trial of 1,800 patients to show the worth of his technique.
Professor David Cunningham of The Royal Marsden said: ‘Radiotherapy is a very important component of effective treatment for patients with many different types of cancer, and the results of this research mean we can deliver this treatment with less adverse effects on the normal, surrounding tissues and organs and is a real advance for patients with prostate cancer.’
The results are published today in the International Journal of Radiation Oncology, Biology, Physics.