Estramustine phosphate compared with diethylstilbestrol. A randomized, double-blind, crossover trial for stage D prostate cancer.
In a double-blind, crossover comparison, 236 patients with metastatic prostate cancer were randomized to receive estramustine phosphate (EMP) or diethylstilbestrol (DES). Previously castrated patients (66) were separately randomized. Patients kept taking their first drug until progression was proved by objective studies, at which time alternative treatment was begun. The primary determinant of efficacy was the duration between start of therapy and date of objective progression. Uncastrated patients treated with EMP had a significantly longer duration without progression than those treated with DES (p less than 0.01). The following subcategories of entry were further evaluated: little or no pain, moderate to severe pain, little reduction in activity, significant reduction in activity, presence or absence of cardiovascular disease, age above or below 70 years, and "good" or "bad" histology. For all but the last category, EMP was statistically superior to DES. Patients who underwent orchiectomy less than 3 months before randomization had nonprogression rates similar to those for noncastrated men in both groups. Secondary (crossover) therapy was less effective than first therapy in both groups: 46% of patients receiving EMP and 40% receiving DES had no progression at 6 months. Clinical and laboratory adverse experiences were similar for both drugs, except that gastrointestinal disturbances were more common in the EMP group.