Abstract B087: Racial disparities in breast cancer survival: Examining the potential role of neighborhood deprivation and breast adipose tissue inflammation

Abstract

Abstract Background: Previous studies have found the Black-White disparity in breast cancer survival is greatest among women living in neighborhoods of high socioeconomic status (i.e., low % poverty). This study aimed to examine the association between race and breast cancer mortality according to neighborhood deprivation, a more comprehensive measure of neighborhood socioeconomic status. We also explored the association between neighborhood deprivation and the presence of breast adipose tissue inflammation as a potential biologic mechanism underlying the association. Methods: We examined Black-White disparities in breast cancer mortality overall and stratified by neighborhood deprivation status among 37,369 Black and White women in the Georgia Cancer Registry who were diagnosed with a first primary Stage I-IIIA breast cancer between 2010 and 2017 and followed until December 31, 2019. Cox proportional hazards regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI). In a separate analysis, we examined the presence of crown-like structures in breast adipose tissue (CLS-B), detected by CD68 immunohistochemistry, among 342 women with stage I–III breast cancer who underwent mastectomy at Emory University Hospitals in Atlanta, Georgia (2007–2012). Logistic regression models were used to estimate odds ratios (OR) and 95% CIs. For both cohorts of breast cancer patients, neighborhood deprivation was assessed dichotomously using census tract at diagnosis and the neighborhood deprivation index (NDI), which was computed using American Community Survey 5-year estimates for census tracts in Georgia. Results: In Georgia, we found Black women with breast cancer had ~1.8 times higher rate of breast cancer mortality than their White counterparts (age-adj. HR=1.78, 95% CI: 1.63, 1.94). The disparity was attenuated after adjusting for stage and molecular subtype but was not eliminated (multivariable (MV)-adj. HR=1.32, 95% CI: 1.21, 1.45). When stratified by NDI, the disparity was greater among women living in neighborhoods of low deprivation (MV-adj. HR=1.44, 95% CI: 1.26, 1.64) compared to high deprivation (MV-adj. HR=1.17, 95% CI: 1.03, 1.33).  Among Emory breast cancer patients, we found high neighborhood deprivation was inversely associated with CLS-B (age- and race-adj. OR=0.48, 95% CI; 0.26, 0.87). We also found Black patients were more likely than their White counterparts to have CLS-B in low deprivation neighborhoods (age-adj. OR=1.79, 95% CI: 0.98, 3.25) but not in high deprivation neighborhoods (age-adj. OR=0.73, 95% CI: 0.24, 2.20), albeit estimates were imprecise. Conclusion: Our study using a population-based cohort of breast cancer patients in Georgia adds to the evidence that racial disparities in breast cancer survival are worse among women living in higher socioeconomic (i.e., low deprivation) neighborhoods. Additionally, we provide evidence of a potential underlying mechanism, finding the prevalence of CLS-B higher for women in low rather than high deprivation neighborhoods, particularly Black women in this group. Citation Format: Maret L. Maliniak, Lauren E. Barber, Jasmine M. Miller-Kleinhenz, Leah Moubadder, Lauren E. McCullough. Racial disparities in breast cancer survival: Examining the potential role of neighborhood deprivation and breast adipose tissue inflammation [abstract]. In: Proceedings of the 16th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2023 Sep 29-Oct 2;Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2023;32(12 Suppl):Abstract nr B087.