A comparison of the following in the treatment of patients with advanced carcinoma of the prostate: 1. DES and cytoxan, Estracyt and cytoxan, versus DES alone in newly diagnosed patients with clinical Stage D disease; 2. Comparison of DES and cytoxan, DES and Estracyt, versus DES alone in patients with Stage D disease who are currently stable on DES. 3. Comparison of methotrexate versus cis-platinum versus Estracyt in patients with Stage D disease who have relapsed following hormonal therapy and who have not received prior radiotherapy. 4. A comparison of Estracyt and cis-platinum versus both agents alone in patients with Stage D disease who have relapsed following hormonal therapy and who have had prior radiotherapy.