LB891 Analysis of Breast Health Outcomes in Women on Oral 5-Alpha Reductase Inhibitors: A Single-Center Retrospective Cohort Study

A retrospective cohort study involving 810 women exposed to oral 5-alpha reductase inhibitors (5ARI) and 5472 matched controls found no significant increase in breast cancer or benign breast disorder risk among those using 5ARI for alopecia treatment. The incidence of breast cancer was 1.6% in the exposed group versus 1.7% in controls, with no significant difference (p = 1.0). Among those exposed, 1.4% of finasteride users and 3.1% of dutasteride users developed breast cancer (p = 0.20). Additionally, 3.7% of exposed women were diagnosed with benign breast disorders compared to 4.8% of controls (p = 0.18). This study suggests that 5ARI use does not increase breast cancer or benign breast disorder risk in women, but further research is needed to confirm these findings.