Intermittent Androgen Suppression as a Treatment for Prostate Cancer: A Review

Prostate cancer continues as the most common malignancy in men in the United States, with a large number of patients presenting with advanced disease. The current treatment for metastatic prostate cancer, permanent androgen withdrawal, is palliative. Patients treated with permanent androgen withdrawal usually relapse and die secondary to prostate cancer's ability to progress to an androgen-independent state of growth. Based on preclinical studies and phase II trials, intermittent androgen suppression (IAS) appears to be a potential alternative to permanent androgen withdrawal. IAS may be a feasible alternative for the treatment of metastatic prostate cancer. In this paper, preclinical studies that form the basis of IAS and the clinical studies to date concerning IAS are reviewed. Through the cycling of reversible androgen suppression, there appears to be recovery of apoptosis and subsequent slower progression to an androgen-independent state. The small clinical studies conducted to date show the feasibility of IAS, and, in a few studies, there appears to be a survival advantage over historic controls. A prospective randomized trial which is currently under way will test IAS as a treatment alternative in stage D&sub2; prostate cancer.