Hiding in plain sight.

In this retrospective VA case control study of over 80K men treated for prostate cancer, those with a >1 year history of pre-diagnosis 5-alpha reductase inhibitor use (e.g., finasteride for BPH or hair loss, n=~8600) were compared to those without such use (n=~72K). Median unadjusted PSA at diagnosis was virtually the same between cohorts, which is concerning since agents like finasteride standardly cut detected PSA in half. This may explain why those on finasteride were roughly twice as likely to have high-risk features at time of diagnosis, conferring a significantly higher prostate-cancer specific mortality. | Sarkar, JAMA Int Med 2019