DOUBLE-BLIND, RANDOMIZED STUDY OF PRIMARY HORMONAL TREATMENT OF STAGED2 PROSTATE CARCINOMA - FLUTAMIDE VERSUS DIETHYLSTILBESTROL

Purpose: Patients with stage D2 prostate carcinoma are often treated i nitially with hormones to decrease endogenous testosterone. Therapy wi th diethylstilbestrol (DES), leuprolide, or bilateral orchiectomy has been reported to be equivalent. DES is the cheapest preparation, but h as the potential for serious cardiovascular or thromboembolic complica tions. Flutamide is a novel antiandrogen with fewer side effects. Pati ents and Methods: The Eastern Cooperative Oncology Group (ECOG) conduc ted a double-blind, randomized study to compare the efficacy of flutam ide (250 mg three times daily) to DES (1 mg three times daily) as the primary hormonal therapy for patients with stage D2 prostate cancer. P atients were stratified by performance status, disease sites, and hist ory of cardiovascular disease at randomization. Results: Forty-eight p atients received DES and 44 flutamide. Patient characteristics were ev enly distributed between the two treatments. The overall response rate was similar (DES, 62%; flutamide, 50%), Grade III or worse cardiovasc ular or thromboembolic toxicity developed in 33.3% of patients on DES and in 17.6% on flutamide (P = .051). Other toxicities were similar be tween the two treatment arms. However, DES produced significantly long er rime to treatment failure (26.4 v 9.7 months, P = .016) and longer survival than flutamide (43.2 v 28.5 months, P = .040). Conclusion: As the primary hormonal therapy for stage D2 prostate cancer, DES caused more serious cardiovascular or thromboembolic complications than flut amide, Despite this, flutamide was not as active an initial agent as D ES. However, the effectiveness of flutamide in conjunction with other agents compared with DES remains undetermined, and the optimal initial hormone therapy of stage D2 prostate cancer requires further studies. (C) 1996 by American Society of Clinical Oncology.