Uptake of Risk Reducing Mastectomy in Older BRCA1/2 and PALB2 Carriers Undergoing Genetic Testing after 60 Years of Age.

The purpose of this study was to evaluate risk-reducing mastectomy (RRM) uptake in older BRCA1/2 and PALB2 carriers who undergo genetic testing after age 60 years. We performed a multicentered retrospective cohort study of all female patients with a confirmed pathogenic variant in BRCA1/2 or PALB2 between 2003 and 2024. Women were categorized as having undergone genetic testing prior to or at/after 60 years of age, with clinical characteristics and risk management strategies compared between groups. Cox Proportional Hazards regression was then used to evaluate factors associated with RRM receipt. Of 814 BRCA1/2 and PALB2 carriers, 102 (12.5%) underwent genetic testing after age 60 years. At a median follow up of 56 months, 36 (35.3%) BRCA1/2 and PALB2 carriers tested over age 60 years underwent RRM. Uptake of RRM varied by personal history of breast cancer; in affected BRCA1/2 and PALB2 carriers, 47.6% of older patients underwent RRM compared with 78.9% of younger carriers (p < 0.001). In unaffected carriers, uptake of RRM was significantly lower among older patients (15.4% versus 40.3%, p = 0.008). In subgroup analysis of older carriers tested after age 60 years, factors associated with higher uptake of RRM included the presence of a BRCA1 or PALB2 variant (p < 0.005), personal history of breast cancer (p < 0.001), and no prior ovarian cancer (p = 0.005). Among BRCA1/2 and PALB2 carriers tested over the age of 60 years, 47.6% of affected carriers and 15.4% of unaffected carriers elected to undergo RRM. Further research evaluating optimal risk-management strategies in older carriers is warranted.