In order to test the hypothesis of complete androgen blockade for advanced prostate cancer (D2CaP), an intergroup trial was instituted in 1985 comparing leuprolide (L) alone to the combination of L with flutamide (F). Eligibility requirements included previously untreated histologically confirmed stage D2CaP, measurable bone or soft tissue metastases, performance status (PS) of 3 or better, acceptable renal and hepatic function, no severe cardiac disease, and no prior or concomitant endocrine therapy. Stratification at entry was on the basis of PS and none or minimal disease (MD) versus severe degree (SD) of bone metastases. Six hundred and seventeen patients were entered into this study between March 1985 and April 1986. At the present time, there is a 3-month difference in the median progression-free survival (13.9 vs 16.9 months; P = 0.039) and a 7.1-month difference in survival (27.9 vs 35.01 months; P = 0.035) favoring L + F. In L + F-treated patients with good PS-MD, the median survival recently has been reached and is 51.9 months vs 39.6 months for L + P patients. The 107 black patients in the study had median survival of 26.4 months vs 33.3 months for whites. Discussions of racial differences in survival as well as other prognostic factors will be presented. The combination of L + F is superior to treatment with L alone. The benefits appear greatest in patients with minimal disease.