Clinical Impact of 21-Gene Recurrence Score Test Within the Veterans Health Administration: Utilization and Receipt of Guideline-Concordant Care.

INTRODUCTION: Ensuring guideline-concordant cancer care is a Department of Veterans Affairs (VA) priority, especially as the number of breast cancer patients at VA medical centers (VAMCs) grows. We assessed the utilization and clinical impact of the 21-gene Recurrence Score test, which predicts 10-year risk of breast cancer recurrence and the likelihood of chemotherapy benefit, on veterans newly diagnosed with breast cancer. PATIENTS AND METHODS: We conducted a retrospective cohort study using 2011-2012 VA Central Cancer Registry, chart review, and laboratory test data. Independent variables assessed included patient and site-of-care characteristics. The outcome of interest was whether newly diagnosed, eligible (node negative, hormone-receptor positive, human epidermal growth factor receptor 2 [HER2] negative) veterans underwent the 21-gene test. We performed descriptive statistics on all patients and multivariate logistic regression to determine associations. We correlated treatments received with test results. RESULTS: Among 328 eligible veterans, 82 (25%) had the 21-gene test; 100 eligible veterans (30%) sought care at a VAMC where no tests were ordered. Receiving care at a VAMC that had women's health services (odds ratio [OR], 1.84, 95% confidence interval [CI], 1.05-3.22) and having tumor characteristics meeting the National Comprehensive Cancer Network 2010 test criteria (OR, 3.06, 95% CI, 1.69-5.57) were positive predictors of testing; increasing age (OR, 0.93, 95% CI, 0.91-0.96 per year) and fee-based care (OR, 0.46, 95% CI, 0.26-0.82) were negative predictors. The majority of tested patients received guideline-concordant care. CONCLUSION: Site of care and tumor characteristics were important predictors of test uptake. Facilitating delivery of guideline-concordant cancer care requires improved laboratory informatics and clinical decision support.