Racial Differences in Response to Neoadjuvant Chemotherapy: Impact on Breast and Axillary Surgical Management

Background Neoadjuvant chemotherapy (NAC), an increasingly used method for breast cancer patients, has the potential to downstage patient tumors and thereby have an impact on surgical options for treatment of the breast and axilla. Previous studies have identified racial disparities in tumor heterogeneity, nodal recurrence, and NAC completion. This report compares the effects of NAC response among non-Hispanic white women and black women in relation to surgical treatment of the breast and axilla. Methods A retrospective review of 85,303 women with stages 1 to 3 breast cancer in the National Cancer Database who received NAC between 1 January 2010 and 31 December 2016 was conducted. Differences in sociodemographic and clinical variables between black patients and white patients with breast cancer were tested. Results The study identified 68,880 non-Hispanic white and 16,423 non-Hispanic black women who received NAC. The average age at diagnosis was 54.8 years for the white women versus 52.5 years for the black women. A higher proportion of black women had stage 3 disease, more poorly differentiated tumors, and triple-negative subtype. The black women had lower rates of complete pathologic response, more breast-conservation surgery, and higher rates of axillary lymph node dissection, but fewer sentinel lymph node biopsies. Axillary management for the women who were downstaged showed more use of axillary lymph node dissection for black women compared with sentinel lymph node biopsy. Conclusions The black patients were younger at diagnosis, had more advanced disease, and were more likely to have breast-conservation surgery. De-escalating axillary surgery is being adopted increasingly but used disproportionately for white women.