Prognostic Variables for Survival in a Randomized Comparison of Treatments for Prostatic Cancer

These data were obtained from a randomized clinical trial comparing four treatments for patients with prostatic cancer in Stages 3 and 4. Stage 3 represents local extension of the disease without evidence of distant metastasis and Stage 4 represents distant metastasis as evidenced by elevated acid phosphatase, x-ray evidence, or both. The trial was double-blinded and the treatments were placebo pill, 0.2 mg diethylstilbestrol, DES, 1.0 mg of DES, or 5.0 mg of DES, all drugs administered daily by mouth. Patients were not required to remain indefinitely on their assigned treatment, but were allowed to have their treatment changed at the discretion of the physician if signs of tumour progression or symptoms appeared. This provision was required for ethical reasons. Patients were followed according to a standard protocol at 6 month intervals or more frequently if required.