A comparison of Zoladex and DES in the treatment of advanced prostate cancer: results of a randomized, multicenter trial

Abstract

This open, prospective study was conducted to compare ZOLADEX (goserelin acetate implant) and diethylstilbestrol (DES) in the treatment of stage D2 prostate cancer. Sixty-seven patients were allocated to receive 3.6 mg of ZOLADEX every 28 days by subcutaneous injection (n = 48) or 3 mg of DES daily by oral administration (n = 19). Median serum levels of testosterone were reduced to castrate levels (less than 50 ng/dl) within one month of therapy in each group and remained so for up to 120 weeks. According to modified criteria of the National Prostatic Cancer Project, 88% of patients in the ZOLADEX group and 84% in the DES group were objective responders. Time to treatment failure and survival were not significantly different between groups, yet the confidence limits for the hazard ratios were wide. ZOLADEX was better tolerated than DES. We conclude that ZOLADEX is an alternative to DES in patients with stage D2 prostate cancer.