The addition of six months of androgen suppression therapy (AST) to radiation therapy improves survival of patients with clinically localized prostate cancer, according to a study in the current issue of the Journal of the American Medical Association.
“Combining three years of AST with 70 Gy RT (dose of radiation therapy) has been shown to improve survival rates for patients with locally advanced prostate cancer,” the authors provide as background information. “However, the toxicity of long-term AST can be significant, particularly in elderly patients.” AST is a treatment that inhibits the release of androgen, the male sex hormone.
Anthony V. D’Amico, M.D., Ph.D., from Brigham and Women’s Hospital, Boston, and colleagues, assessed the survival benefit of 3-dimensional conformal radiation therapy (3D-CRT) alone or in combination with 6 months of AST in patients with clinically localized prostate cancer. The 206 patients were randomized to receive 70 Gy 3D-CRT alone (n=104) or in combination with 6 months of AST (n = 102) from December 1, 1995 to April 15, 2001. The patients included those with a prostate specific antigen (PSA) of at least 10 ng/mL, a Gleason score (grading system for prostate cancer) of at least 7, or radiographic evidence of disease outside the prostate. Follow-up visits were performed at the end of radiation treatment every 3 months for 2 years, every 6 months for an additional 3 years, and then annually until death or January 15, 2004, the end of the study.