A total of 327 patients with metastatic prostate cancer were randomized to receive bilateral orchiectomy or treatment with Zoladex and flutamide. The trial aimed to evaluate subjective and objective time to progression, survival, and incidence and duration of response. Strict quality control and evaluation by independent ad hoc committees were organized. Progression was assessed for each of 13 parameters. The time to subjective and objective progression was in favor of the combination treatment, with statistical significances of P = 0.009 and P = 0.008, respectively. This delay in objective progression resulted in increased survival in favor of the combination treatment for death by cancer (P = 0.02) or overall survival (P = 0.05). Survival differences were more marked in the patients with better prognostic factors. The clinical significance of these differences for the individual patient requires detailed assessment.