Five-Alpha-Reductase Inhibitors for Prostate Cancer Prevention

The Cochrane review from 2008 evaluated the use of 5-alpha-reductase inhibitors (5ARIs), such as finasteride and dutasteride, in preventing prostate cancer in 34,410 men across nine trials. The review found that 5ARIs were associated with a 26% relative risk reduction in prostate cancer detected for cause, with an absolute risk reduction of 1.4%. However, there was an increased incidence of high Gleason score tumors in men taking finasteride. Side effects, particularly related to sexual and erectile function, were more common with finasteride than placebo. The review concluded that while 5ARIs can reduce the risk of prostate cancer, they may also increase the risk of high-grade disease, and their impact on prostate cancer mortality was unclear, necessitating further research.