In a recent study funded by grants from the National Cancer Institute and published in the New England Journal of Medicine, it was reported that short-term androgen-deprivation therapy improves survival in men with intermediate-risk, localized prostate cancer. From 1994 to 2001, one thousand seventy nine men with localized prostate cancer and prostate-specific antigen levels of 20 ng/mL or less were randomized to receive radiotherapy alone (992 patients) or radiotherapy plus four months of androgen-deprivation therapy (987 patients).
The overall ten-year survival rate was significantly higher with combination therapy than with radiation alone, and combination therapy decreased disease-specific deaths. The median follow-up period was 9.1 years, and the ten-year rate of overall survival was 62% among patients receiving radiotherapy plus short-term ADT (the combined-therapy group), as compared with 57% among patients receiving only radiotherapy. The addition of short-term ADT was associated with a decrease in the 10-year disease-specific mortality from eight percent to four percent. Biochemical failure, distant metastases, and the rate of positive findings on repeat prostate biopsy at two years were significantly improved with radiotherapy plus short-term ADT. In the two groups, acute and late radiation-induced toxic effects were similar.
The study was carried out because it had not been known whether short-term androgen-deprivation therapy (ADT) before and during radiotherapy improves cancer control and overall survival among patients with early, localized prostate adenocarcinoma.
It was found in a post-hoc analysis that the benefits of combination therapy were limited to men with intermediate-risk disease rather than men with low-risk cancer.