PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: No prior cytostatic chemotherapy Endocrine therapy: At least 1 month since antiandrogens Prior hormonal therapy required Radiotherapy: No radiotherapy within the past 4 weeks No radiotherapy to the lesions used to evaluate activity of the study drug Surgery: Prior orchiectomy allowed Other: No other investigational drugs during the last month No prior therapy with cytostatic agents