5-Alpha-Reductase Inhibitors for Prostate Cancer Chemoprevention: An Updated Cochrane Systematic Review

The 2010 Cochrane systematic review found that 5-α-reductase inhibitors (5-a-RIs) like finasteride and dutasteride reduce the risk of prostate cancer diagnosis by 25% to 26% in men undergoing regular screening, with a greater absolute risk reduction for cancers detected for-cause than for overall prostate cancers. The review included eight studies, with a focus on the PCPT and REDUCE trials, involving men with a mean age of 64 and a mean PSA level of 3.1 ng/mL. However, these medications were associated with increased sexual and erectile dysfunction. The review highlighted a consistent risk reduction in men with baseline PSA levels below 4.0 ng/mL, but not in those with higher levels. There was no significant difference in high-grade tumors or mortality rates between 5-a-RIs and placebo. The document emphasized the need for further research to assess the long-term impact on morbidity and mortality, and the effects of 5-a-RIs on PSA levels and prostate biopsy indications.