Evaluation of Germline Genetic Testing Criteria in a Hospital-Based Series of Women With Breast Cancer.

Abstract

To determine the sensitivity and specificity of genetic testing criteria for the detection of germline pathogenic variants in women with breast cancer. Women with breast cancer enrolled in a breast cancer registry at a tertiary cancer center between 2000 and 2016 were evaluated for germline pathogenic variants in 9 breast cancer predisposition genes (<i>ATM</i><i>, BRCA1, BRCA2, CDH1, CHEK2, NF1, PALB2, PTEN</i>, and <i>TP53</i>). The performance of the National Comprehensive Cancer Network (NCCN) hereditary cancer testing criteria was evaluated relative to testing of all women as recommended by the American Society of Breast Surgeons. Of 3,907 women, 1,872 (47.9%) meeting NCCN criteria were more likely to carry a pathogenic variant in 9 predisposition genes compared with women not meeting criteria (9.0% <i>v</i> 3.5%; <i>P</i> < .001). Of those not meeting criteria (n = 2,035), 14 (0.7%) had pathogenic variants in <i>BRCA1</i> or <i>BRCA2.</i> The sensitivity of NCCN criteria was 70% for 9 predisposition genes and 87% for <i>BRCA1</i> and <i>BRCA2</i>, with a specificity of 53%. Expansion of the NCCN criteria to include all women diagnosed with breast cancer at ≤ 65 years of age achieved > 90% sensitivity for the 9 predisposition genes and > 98% sensitivity for <i>BRCA1</i> and <i>BRCA2</i>. A substantial proportion of women with breast cancer carrying germline pathogenic variants in predisposition genes do not qualify for testing by NCCN criteria. Expansion of NCCN criteria to include all women diagnosed at ≤ 65 years of age improves the sensitivity of the selection criteria without requiring testing of all women with breast cancer.