Benefit of combining radiation and hormone therapy in the treatment of prostate cancer

Nov 1 2005

Doctors in Canada have discovered that treating high-risk prostate cancer patients with radiation therapy and adding hormone therapy for more than one year allows patients to live longer, have better control of their prostate specific antigen levels and lowers the rate of death specifically from prostate cancer, according to a study published in the November 1, 2005, issue of the International Journal of Radiation Oncology-Biology-Physics, the official journal of ASTRO.

A total of 307 patients with a PSA level greater than 20 were split into two groups, both with a similar demographic of age, Gleason score and tumor stage. The first group had 151 patients receiving hormone therapy for less than 12 months (short term) and the second set had 156 patients receiving hormone therapy for more than 12 months (long term). Both groups were treated with hormone therapy in conjunction with external beam radiation therapy.

In the long-term hormone therapy group, 62.5 percent of patients showed a greater control over their PSA level, compared with 37 percent in the short-term group. The five-year overall survival rate was 87.5 percent for the long-term group and 75 percent in the short-term group. The chance of dying of prostate cancer was reduced from 18 percent to 6 percent in the long-term group.

"Other randomized trials have shown the benefit of combining radiation and hormone therapy in the treatment of prostate cancer. However, some of those reports appear to be restricted to patients with a high Gleason score," said Eric Berthelet, M.D., lead author of the study and a radiation oncologist at the BC Cancer Agency in Victoria, British Columbia, Canada. "This study proves that long-term hormone therapy used in consort with radiation therapy improves survival rates for high-risk patients, regardless of their Gleason score or tumor stage."