Patterns of Practice of Nodal Radiation Therapy in Breast Cancer: Results of the EORTC “NORA” Survey

Purpose/Objective(s): To compare the racial differences in treatment and overall survival (OS) of male breast cancer (MBC) patients. Materials/Methods: Data were extracted from the NCI SEER database that included 18 population-based registries from 1988-2010. Chi-square test, Kaplan-Meier method, and Cox regression models were employed in SPSS 20.0 for data analyses. Results: A total of 4,279 MBC patients were identified. The median age was 65 years. A total of 3,266 (76.3%) patients were White, 552 (12.9%) Black, 246 (5.7%) Hispanic, and 215 (5.0%) were Asian. Compared to other races, Black patients were more likely to be diagnosed at a younger age (p < 0.001), have advanced stage disease (p Z 0.001), not be married (p < 0.001), and less likely to undergo lymph node dissection (p Z 0.006). When stratified by stage, there was no difference in receipt of primary treatment by race. The 5-year OS for the cohort was 73.4%. The 5-year OS for White, Black, Hispanic, and Asian races was 73.8%, 66.3%, 74.0%, and 85.3%, respectively (p < 0.001). This significant worse 5-year OS for Blacks persisted regardless of age, in those with invasive ductal cancers, ER+/PR+ cancers, nodal metastases, stage II or III disease, and grade 2 or 3 disease, and in those who underwent modified radical mastectomy, lymph node dissection and adjuvant radiation therapy. On multivariate analysis, Black race, older age at diagnosis, earlier year of diagnosis, not receiving mastectomy or lymph node dissection, having advanced stage of disease, and higher tumor grade were independent prognostic factors for worse OS. Conclusions: Race remains an independent prognostic factor for OS in male patients with breast cancer, with Black patients experiencing significantly poorer 5-year OS. Blacks were less likely to receive lymph node dissection of which patients may derive benefit, though we did not observe receipt of primary treatment, after stratifying for disease stage, to be an underlying factor contributing to racial outcome differences. Further studies are warranted to evaluate causes for these racial disparities including socioeconomic status, access to medical care, limiting medical co-morbidities, and genetic profiles. Author Disclosure: J. Shin: None. L.A. Kachnic: None. A. Hirsch: None.