RESUMEN
BACKGROUND: Completion of surgical resection and adjuvant/neoadjuvant treatments (chemotherapy, radiation, and endocrine therapy) is necessary to achieve optimal outcomes in invasive breast cancer. The objective of this study was to determine the characteristics of patients refusing treatment and to analyze the impact of refusal on survival. STUDY DESIGN: A retrospective cohort study of invasive breast cancer cases diagnosed 2004-2016 was performed utilizing the National Cancer Database. RESULTS: Of 2 058 568 cases comprising the study cohort, .6% refused recommended surgery, 14.1% refused chemotherapy, 5.5% refused radiation, and 6.3% refused endocrine therapy. Patients refusing therapy were older and more likely uninsured; they did not live farther from the treating hospital. Racial disparities were also associated with refusal. Surgery refusal had the highest hazard ratio for mortality (2.7; 95% CI: 2.5-3.0, P < .001) compared to chemotherapy (1.3; 95% CI: 1.3-1.4, P < .001), radiation (1.8; 95% CI: 1.7-1.9, P < .001), and endocrine therapy (1.5; 95% CI: 1.4-1.6, P < .001) independent of race, insurance, receptor status, and stage. CONCLUSION: This study demonstrates significant associations with refusal of breast cancer treatment and quantifies the impact on mortality, which may help to identify at-risk groups for whom interventions could prevent increases in mortality associated with declining treatment.