A prospective study was conducted to evaluate response rate and toxicity of the combination of cyclophosphamide, adriamycin, and cis-platinum in patients with disseminated hormonally resistant prostatic carcinoma. Twenty-two patients were entered in the study: 19 were evaluable for response. One patient achieved partial remission while 14 (73%) had stable disease. Four patients had progressive disease. Patients with stable disease and partial remission had subjective improvement and survived significantly (p less than 0.03) longer than patients with progressive disease (58 weeks vs. 22 weeks). Toxicity was mainly hematological, and one patient died from sepsis secondary to leukopenia. Nausea and vomiting was moderate to severe, with one patient refusing cis-platinum for that reason. Renal toxicity was tolerable and reversible. Lack of good measurable disease makes generalization difficult, but pointers from animal models, along with the biological activity suggested by our results, make this a worthwhile combination to be considered for a trial in a larger population with measurable disease or in a randomized trial vs. the more effective single agent.