Evaluating the NCCN clinical criteria for recommending BRCA1 & BRCA2 genetic testing in patients with breast cancer

Abstract

Background: Mutations in the BRCA1 and BRCA2 genes predispose individuals to a significantly elevated risk for breast and ovarian cancers. Identification of these individuals allows for proper screening, management, and testing of at-risk relatives. NCCN has established clinical criteria for recommending BRCA1/2 testing. Patients and Methods: A retrospective chart review of 1,123 patients with breast cancer was performed to evaluate the positive predictive values (PPVs) of 14 individual criteria for predicting BRCA1/2 mutations. Results: Two criteria had PPVs significantly below 10%. Only 2 of 115 patients who were recommended for testing based solely on the criterion of "diagnosed with breast cancer at ≤45 years of age" had pathogenic mutations at a PPV of 1.6% (95% CI, 0.2%-6.0%). Additionally, 0 of 37 individuals who underwent testing based on the criterion, "diagnosed with breast cancer at any age with ≥2 close blood relatives with breast cancer at any age" tested positive (95% CI, 0%-9%). Overall, meeting >1 criterion has a PPV of 12%, whereas meeting only 1 criterion has a PPV of 3.2% (95% CI, 1.6%-5.7%), significantly below 10% (P 1 criterion constitute a population significantly enriched for BRCA1/2 mutations, whereas those meeting only 1 criterion test positive at a rate similar to unselected patients with breast cancer. These data will inform ongoing discussions regarding how to best implement BRCA1/2 genetic testing.