Finasteride as a chemopreventive agent in prostate cancer: impact of the PCPT on urologic practice

Abstract
The results of the Prostate Cancer Prevention Trial (PCPT) sparked a debate surrounding the advantages and disadvantages of using the 5-alpha reductase inhibitor finasteride as a chemoprevantative agent against prostate cancer. Over three years after the publication of the PCPT results there is still a reluctance to recommend the use of finasteride in this setting. This Review examines the PCPT data and discusses its results in light of further studies. Prostate cancer chemoprevention involves the use of natural and/or synthetic agents that inhibit or reverse the development of precancerous lesions or delay progression of these lesions to invasive disease. The recent completion of the first Phase III trial for prostate cancer prevention, the Prostate Cancer Prevention Trial (PCPT) using the drug finasteride, has provided the urologic community with the first evidence that a chemopreventive agent can reduce the risk of developing prostate cancer. The enthusiasm for the clear relative risk reduction in the finasteride arm of the trial has been tempered by the observation that the incidence of high-grade tumors was higher in men receiving finasteride compared to those on placebo. A question remains about whether the observed higher incidence in high-grade tumors is real or whether it is related to a pathologic or sampling artifact. The PCPT has instigated a great deal of debate, resulting in the larger urologic community being reluctant to recommend the widespread use of finasteride as a chemopreventive agent. This review summarizes the PCPT, analyzes its controversial results, and describes future prostate cancer chemoprevention studies.