Multi-Gene Hereditary Cancer Testing Among Men With Breast Cancer.

1532Background: All men with a personal diagnosis of breast cancer (BC) are candidates for BRCA1/2 genetic testing, as pathogenic variants (PVs) in these genes have a known association with BC risk in both men and women. As additional genes with known BC risk in women are now routinely included in multi-gene panel testing, we evaluated the outcomes of multi-gene panel testing in a large cohort of men with BC. Methods: This analysis includes the results of commercial genetic testing for 1,358 men with BC usinga multi-gene pan-cancer panel between September 2013 and January 2017. Clinical information was obtained from provider-completed test request forms. Age at diagnosis, personal, and family history were compared for men with PVs in BRCA1/2 versus non-BRCA1/2 genes. Results: Overall, 207 (15.2%) men with BC were found to carry a PV, where 147 (10.8%) men had a PV in BRCA1/2 (BRCA1, 0.7%; BRCA2, 10.2%) and 60 (4.4%) men had a PV in a non-BRCA1/2 gene (CHEK2, 2.0%; ATM, 1.0%; PALB2, 1.0%; BARD1, 0.2%; NBN,...