Purpose: To evaluate factors associated with compliance to the National Comprehensive Cancer Network (NCCN) guidelines for BRCA1/2 testing and identify groups who are at risk of under- and over-use of BRCA1/2 testing.
Methods: Data included 20,758 women from Dr. Susan Love Research Foundation's The Health of Women (HOW) Study®. Multinomial logistic regression was used to examine the association of socioeconomic and demographic characteristics with whether the woman was over-, under-, or appropriately tested for BRCA1/2 mutations, per 2015 NCCN guidelines.
Results: 3894 women (18.8%) reported BRCA1/2 testing. 5628 (27.1%) women who met NCCN criteria for testing were not tested. Among women with a history of breast cancer, those without health insurance were more likely to be under-tested (OR 2.04, 95% CI 1.15-3.60) than those with managed care insurance, and higher education was associated with a lower likelihood of under-testing (Graduate/professional degree OR 0.71, 95% CI 0.55-0.91).
Conclusion: Almost 30% of women were under-tested, indicating that many high-risk women who may benefit from genetic testing are currently being missed. Without appropriate testing, providers are unable to tailor screening recommendations to those carrying mutations who are at highest risk. Patient and healthcare provider education and outreach targeted to low-income and under-served populations may assist in reducing under-testing.
Keywords: BRCA1/2; Breast cancer; Genetic testing; Guideline adherence.