Exploring the intersectionality of race/ethnicity with rurality on breast cancer outcomes: SEER analysis, 2000–2016

Purpose: Disparities in breast cancer survival have been observed within marginalized racial/ethnic groups and within the rural–urban continuum for decades. We examined whether there were differences among the intersectionality of race/ethnicity and rural residence on breast cancer outcomes. Methods: We performed a retrospective analysis among 739,448 breast cancer patients using Surveillance Epidemiology and End Results (SEER) 18 registries years 2000 through 2016. We conducted multilevel logistic-regression and Cox proportional hazards models to estimate adjusted odds ratios (AORs) and hazard ratios (AHRs), respectively, for breast cancer outcomes including surgical treatment, radiation therapy, chemotherapy, late-stage disease, and risk of breast cancer death. Rural was defined as 2013 Rural–Urban Continuum Codes (RUCC) of 4 or greater. Results: Compared with non-Hispanic white–urban (NH-white–U) women, NH-black–U, NH-black–rural (R), Hispanic–U, and Hispanic–R women, respectively, were at increased odds of no receipt of surgical treatment (NH-black–U, AOR = 1.98, 95% CI 1.91–2.05; NH-black–R, AOR = 1.72, 95% CI 1.52–1.94; Hispanic–U, AOR = 1.58, 95% CI 1.52–1.65; and Hispanic–R, AOR = 1.40, 95% CI 1.18–1.67), late-stage diagnosis (NH-black–U, AOR = 1.32, 95% CI 1.29–1.34; NH-black–R, AOR = 1.29, 95% CI 1.22–1.36; Hispanic–U, AOR = 1.25, 95% CI 1.23–1.27; and Hispanic–R, AOR = 1.17, 95% CI 1.08–1.27), and increased risks for breast cancer death (NH-black–U, AHR = 1.46, 95% CI 1.43–1.50; NH-black–R, AHR = 1.42, 95% CI 1.32–1.53; and Hispanic–U, AHR = 1.10, 95% CI 1.07–1.13). Conclusion: Regardless of rurality, NH-black and Hispanic women had significantly increased odds of late-stage diagnosis, no receipt of treatment, and risk of breast cancer death.