A major five-year study has found that combining a course of hormonal therapy with standard radiotherapy is an effective way to combat advanced forms of the disease.

The study, undertaken by the European Organization for Research and Treatment of Cancer (EORTC), involved more than 400 patients with locally advanced prostate cancer.

The patients either received standard radiotherapy alone or in combination with a three-year course of Zoladex, given by monthly injection.

The researchers found that the combination therapy was well tolerated and boosted survival rates from 62% to 78%.

Professor Michel Bolla, head of radiotherapy at the Hospital of the University of Grenoble in France and president of the EORTC radiotherapy group, told the European Cancer Conference in Vienna that the results could lead to a significant change in the way prostate cancer is treated.

He said: "Prostate cancer kills tens of thousands of men world-wide each year and the number of new cases being diagnosed continues to rise.

"While many clinicians already combine these two treatment approaches for patients with locally advanced disease, the practice is by no means systematic.

"Our study suggests that combining radiotherapy with hormonal treatment could save thousands of lives."

Testosterone causes cancer

Zoladex, or goserelin acetate, inhibits the production of the male sex hormone testosterone by the testes.

Testosterone stimulates the growth and proliferation of prostate cancer cells.

By halting testosterone production, goserelin can control the spread of prostate cancer in advanced disease and help stop the cancer recurring when used in combination with radiotherapy in locally advanced disease.

The prostate is a gland that forms part of the male reproductive system.

Its function is not fully understood, but the prostate contributes secretions to semen as it collects prior to ejaculation.

Prostate cancer is the most common form of cancer in men, excluding skin cancer, and is the second leading cause of cancer death.

The rate of prostate cancer has increased considerably throughout the world over the past two decades.

The disease commonly occurs in men above the age of 50 years, and the incidence rises sharply between the ages of 60 and 80 years.