The specific objective of this cooperative research project is to evaluate clinical effectiveness of chemotherapeutic agents in the treatment of patients with advanced prostatic cancer who have failed to respond or are no longer responding to existing hormonal therapy. Patients from the several cooperating institutions will be randomized to various treatment groups under the Protocols being operated at that time. By using similar patients from several institutions the project will be able to evaluate potential agents in the treatment of prostatic carcinoma more rapidly than any single institution alone. Currently two Protocols have been completed; Protocl 100, 5-Fluorouracil and Cyclophosphamide compared to Standard treatment, and Protocol 200, Estracyt and Streptozotocin compared to Standard treatment. Presently Protocol 300 is comparing Procarbazine and DTIC with Cyclophosphamide, and Protocol 400 is comparing Estracyt with Leo 1031 to Leo 1031 alone. Protocol 500 is comparing cyclophosphamide plus Estracyt to Cyclophosphamide plus Diethylstilbestrol to Diethylstilbestrol or hormonal manipulation alone, in patients who have not previously been treated for their disease. Protocol 600 uses these same agents in patients with newly discovered disease. Protocols mentioned above and new Protocols being brought out as old ones are filled as they are available from any of the participating institutions. Basic decisions to evaluate other chemotherapeutic agents will be made by the members of the National Prostatic Cancer Project in council with the National Cancer Institute. BIBLIOGRAPHIC REFERENCES: Schmidt, J.D., Johnson, D.E., Scott, W.W., Gibbons, R.P., Prout, G.R., and Murphy, G.P.: Chemotherapy of Advanced Prostatic Cancer, Evaluation of Response Parameters. Urology, 7:602-610, 1976. Murphy, G.P., Saroff, J., Joiner, J.R., Prout, G.R., Gibbons, R.P., Schmidt, J.D., Johnson, D.E., and Scott, W.W.: Chemotherapy of Advanced Prostatic Cancer by the National Prostatic Cancer Group. Seminars in Oncology, 3:103-106, 1976.