Incidence of cardiovascular disease and death in patients receiving diethylstilbestrol for carcinoma of the prostate

Patients treated with a 5.0-mg daily dose of diethylstilbestrol (DES) had an increased incidence of fatal and non-fatal cardiovascular disease when compared to placebo in all stages of prostatic cancer (p < 0.025). The pretreatment cardiovascular status of estrogen-treated patients was generally better than those treated with placebo. Therapy with DES 5.0 mg did not increase survival of Stage III or IV patients significantly when compared to placebo. The decrease in cancer mortality associated with the 5.0-mg dose of DES was offset by an increase in deaths from cardiovascular causes. Early endocrine treatment of patients with asymptomatic Stage III carcinoma is not indicated. Endocrine therapy should be started early only in Stage IV patients. When DES is preferred, it should be administered in a dose lower than 5.0 mg. Complications of estrogen therapy may be due to an increased incidence of thromboembolism.