A long-term clinical trial has shown that a high-tech form of radiation can “dramatically” improve outcomes for patients with prostate cancer.

The trial, led by The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research, found 71 per cent of patients were alive and disease-free five years after treatment.

They include Worcester Park resident, William Burley, 76, who was diagnosed with prostate cancer in 2007.

A PSA test to screen for prostate cancer revealed his score was “through the roof.”

Months after being diagnosed William was advised to go on the intensity-modulated radiation therapy (IMRT) trial at The Royal Marsden.

He told Sutton Guardian: “It was a four week programme as opposed to seven weeks for the ordinary radiotherapy.

“After the IMRT my PSA reading went to almost nothing.”

IMRT is designed to focus on pinpointing the tumour with nearby tissues being spared.

William is now free of cancer and would recommend for others to consider IMRT.

"It seems to have killed my cancer," he said. "I’m healthy and I can now carry on with the sports I enjoy like swimming and cycling.”

The study by The Royal Marsden and the ICR was one of the first examinations of IMRT.

Leader of the study, Professor David Dearnaley, said: “This technique has already proven to be a game changer for men with prostate cancer and the work done here has already been carried forward into later-stage phase II and phase III trials.

“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 in using this technique. 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.”

Chief Executive of the Institute of Cancer Research, Paul Workman, added: “It’s great to see this long-term evidence of the degree to which precision radiotherapy has transformed outcomes for men with prostate cancer.”

The clinical test established the safety of giving IMRT to the pelvic lymph nodes with more work required to fully determine how effective the treatment is.