Estrogens in the Treatment of Prostate Cancer

Abstract

Purpose The history, mechanisms of action, efficacy and complications of estrogen therapy for prostate cancer are reviewed, and the current and future roles of estrogens in the treatment of prostate cancer are addressed. Materials and Methods An extensive review of the literature was done. Results Estrogens are effective in the treatment of advanced prostate cancer. High dose oral estrogens are associated with an increased risk of cardiovascular death. A dose of 1 mg. diethylstilbestrol daily is not associated with an increased risk of cardiovascular death. Estrogens are associated with other toxicities. Parenteral estrogens may not have the risk of cardiovascular death that is ascribed to oral estrogens. Estrogens have not been adequately compared to the combined androgen blockade regimen. Conclusions A 1 mg. dose of diethylstilbestrol remains a medical alternative to bilateral orchiectomy in the treatment of advanced prostate cancer. Doses of 3 mg. diethylstilbestrol or more have a prohibitively high risk of cardiovascular death. Further studies comparing the efficacy, complications and cost of regimens containing oral estrogens or parenteral estrogens with agents that increase efficacy (for example antiandrogens) and decrease toxicity (for example anticoagulants) to results of other regimens, such as combined androgen blockade, should be done to determine if an estrogen-containing regimen could lower the cost of treating advanced prostate cancer.