An international study has shown a four-week high-dose radiation therapy for prostate cancer is just as good as the standard eight-week treatment regimen.

A new, potent form of radiation therapy for men with prostate cancer halves treatment time, a study has shown.

Australian researchers are celebrating the results of an international clinical trial which has shown radiation therapy for prostate cancer can safely be compressed from a standard eight weeks of daily treatment down to four weeks with the same cure rate and no difference in side effects.

This means men may undergo 20 treatments rather than the previous 39-40.

Associate Professor Jarad Martin, of the Calvary Mater Newcastle, is the Australian Trial Chair of the Trans Tasman Radiation Oncology Group (TROG) and says duration of treatment is a major issue for many patients.

"The message from them is that the shorter the treatment period the better," Ass Prof Martin said.

He says this study potentially opens the door to giving a slightly bigger dose each day and completing the treatment faster.

"Radiation therapy is a proven treatment option for many men diagnosed with prostate cancer," he said.

"Treatment is safe, effective, non-invasive and done as an outpatient. With modern techniques the risk of side effects is low.

"A standard course is often given five days a week over eight weeks, which can make treatment challenging for some men. This is especially true if they live in regional parts of Australia."

The international study published in the Journal of Clinical Oncology involved more than 1200 men with a common type of prostate cancer.

They were randomly selected to receive either standard radiotherapy over eight weeks or a higher dose, known as Hypofractionated radiotherapy, over four weeks.

After several years of monitoring these men, Ass Prof Martin and his collaborators have announced that there was no difference between cure rates or side effects between the two groups.

According to the findings, 85 per cent of patients in both groups had no signs of cancer five years after treatment.

On the basis of this long-awaited information, many Australian cancer centres are now beginning to offer a four-week radiation therapy program as a standard treatment option for men with prostate cancer.

"Patients will sometimes hesitate if told the radiation treatment could last two months. But now we can offer treatment that lasts just four weeks and many patients are opting for that," said Ass Prof Martin