Beyond BRCA: Patterns of risk-reducing surgery for non-BRCA, homologous recombination repair pathway gene variant carriers.

OBJECTIVE: The real-world management of patients with non-BRCA, homologous recombination repair pathway variants with increased or uncertain risks of ovarian cancer is unknown. The objective was to determine the adoption of risk-reducing salpingo-oophorectomy (RRSO) for carriers of variants with increased or uncertain risks of ovarian cancer beyond BRCA. METHODS: This was a retrospective cohort study of patients at three hospitals with non-BRCA, homologous recombination repair pathway variants with increased risk (BRIP1, RAD51C, RAD51D) and uncertain risk (ATM, BARD1, NBN, PALB2) of ovarian cancer. Outcomes of interest were adoption of RRSO and factors associated with adoption of RRSO. Wilcoxon rank-sum, chi-square, and logistic regression were performed with p < 0.05. RESULTS: Of 318 patients, 76 (24%) had pathogenic variants with increased risks of ovarian cancer (BRIP1, 45; RAD51C, 20; RAD51D, 11), and 242 (76%) had variants with uncertain risks of ovarian cancer (ATM, 145; PALB2, 69; NBN, 23; BARD1, 5). Of 64 patients eligible for RRSO by National Comprehensive Cancer Network (NCCN) criteria or family history, 31 (48%) underwent RRSO. Among eligible patients who did not undergo RRSO, 24 (73%) were not referred for gynecologic oncology consultation. Older age at testing (adjusted odds ratio [aOR] 1.08, 95% confidence interval [CI] 1.03-1.13) and referral to gynecologic oncology (aOR 33.48, CI 8.10-138.39) were associated with increased adoption of RRSO when adjusting for personal and family history of breast and ovarian cancer. CONCLUSION: Half of RRSO-eligible patients by NCCN criteria beyond BRCA did not undergo RRSO. Opportunities exist for improving education to increase referrals to facilitate RRSO for these patients.