The Use of 5α-Reductase Inhibitors for the Prevention and Treatment of Prostate Cancer

Abstract

The potential use of 5a-reductase inhibitors (5-ARIs) for the prevention and treatment of prostate cancer (PCa) is currently under considerable study. After the analysis of a large randomized controlled trial (RCT) of finasteride for the primary chemoprevention of PCa and other RCTs examining 5-ARIs, the American Society of Clinical Oncology and the American Urological Association issued a joint guideline in 2008 recommending consideration of 5-ARIs for PCa prevention [1]. Since then, another large RCT reported that dutasteride also decreased the risk of PCa [2]. Nevertheless, the Oncologic Drugs Advisory Committee of the US Food and Drug Administration (FDA) recently rejected applications for PCa chemoprevention labeling for both finasteride and dutasteride. Should enthusiasm for research involving the use of 5-ARIs in PCa be diminished? We think not. The potential uses of 5-ARIs in PCa include not only primary chemoprevention but also what has been termed secondary prevention (delay of pathologic progression to clinically significant disease or progression to active treatment) in active surveillance protocols, use following biochemical failure after primary therapy, and inmetastatic disease. An interesting study by Finelli et al. [3] provides additional exciting data in the secondary prevention setting. These results, coupled with those from large ongoing RCTs, should be evaluated before deciding on a final verdict for the use of 5-ARIs in a variety of different settings related to PCa. Finelli et al report on a retrospective review of patients at their institution undergoing active surveillance for PCa stratified by 5-ARI use [3]. After excluding men who had been on a 5-ARI before an initial diagnostic biopsy, they identified 70 patients who were started on a 5-ARI at some