Abstract
BACKGROUND: Women diagnosed with triple-negative (ER-, PR-, HER2-) breast cancer (TNBC) have poor survival outcomes compared with other breast cancer subtypes. Yet there is little nonexperimental data on whether guideline-concordant therapy translates to better outcomes over time, or about factors associated with receipt of such guideline care. This study addresses these issues. METHODS: Using data from the Centers for Disease Control and Prevention National Program of Cancer Registries (NPCR) augmented via medical records abstraction, the authors constructed a cohort of women diagnosed with invasive, nonmetastatic (stage I-III) TNBC in 2004 (N = 747) and followed through 2015. The date and primary cause of death were derived from the NPCR and the National Death Index. Standard-of-care treatment (as aligned with the study's timeframe) was defined as being guideline concordant (GC) for surgery, radiation therapy, and chemotherapy based on appropriate initiation, regimen, and completion. Through regression modeling, the authors examined predictors of being GC and the association of GC with 10-year survival outcomes. RESULTS: Controlling for patient, tumor, and sociodemographic factors, patients whose management was GC had significantly better all-cause survival (hazard ratio [HR], 0.59; 95% confidence interval [CI], 0.45-0.77), breast cancer-specific survival (HR, 0.60; 95% CI, 0.42-0.86), and also better non-breast cancer survival (HR, 0.63; 95% CI, 0.40-1.00), compared with those whose management was Not GC. Treatment at a Commission on Cancer-accredited facility was a significant predictor of receiving GC care (odds ratio, 1.87; 95% CI, 1.34-2.59). CONCLUSION: Building on this study's methodology and its findings about the effectiveness of long-standing approaches to TNBC management, additional population-based studies are urgently needed as new therapeutic approaches are being integrated into guidelines and clinical practice.