Differences in breast cancer outcomes amongst Caribbean born women in Florida, USA-a population-based analysis.

Background: Black women face the highest global burden of breast cancer mortality. Caribbean countries also experience the greatest burden of breast cancer mortality worldwide. In this study, we examined how sociodemographic and clinical factors shape presentation and overall survival among Caribbean born immigrants with breast cancer in Florida. Methods: We performed a population-based cohort study of breast cancer cases diagnosed between 1981 and 2020 from the Florida Cancer Data System (FCDS). Eligible women were diagnosed with invasive breast cancer and categorized as Black women born in The Bahamas, Cuba, Dominican Republic, Haiti and Jamaica; US-born Black women (USBB) and US-born White women (USBW). Multivariable Cox proportional hazard regression estimated adjusted hazard ratios (aHR) for all-cause overall survival. Models were adjusted for age, insurance, estrogen receptor status, stage, grade, receipt of surgery, radiation, chemotherapy, hormonal therapy, and race/country of birth (nativity). Findings: Among 179,992 women (mean [SD] age, 62.84 [13.90] years), there were 17,345 (9.6%) US-born Black women; 358 (0.2%) Bahamian-born; 241 (0.1%) Cuban-born; 182 (0.1%) Dominican-born; 2267 (1.3%) Haitian-born; 2335 (1.3%) Jamaican-born and 157,264 (87.4%) US-born White women. In multivariable Cox regression, US-born Black women had shorter survival compared to Cuban-born women (aHR:0.49 95% CI [0.33-0.71]), Dominican-born women (aHR:0.61 95% CI [0.39-0.95]), US-born White women (aHR:0.73 95% CI [0.70-0.77]) and Jamaican-born women (aHR:0.81 95% CI [0.72-0.92]) and there was no difference when compared to Haitian-born women (aHR:0.92 95% CI [0.82-1.03]). In estrogen receptor positive tumors, US-born Black women had shorter survival compared to Cuban-born women (aHR:0.61 95% CI [0.39-0.95]) and Dominican-born women (aHR:0.59 95% CI [0.36-0.97]). In estrogen receptor negative tumors, US-born Black women had shorter survival compared to Cuban-born women (aHR:0.22 95% CI [0.07-0.68]) and Jamaican-born women (aHR:0.78 95% CI [0.64-0.96]). Interpretation: Black women in Florida-USA, present significant heterogeneity in breast cancer outcomes based on nativity. There are significant differences in survival within the Caribbean Black immigrant population in Florida. US-born Black women had shorter survival overall and in estrogen receptor positive breast cancer, while Jamaican-born women had longer survival in estrogen receptor negative breast cancer. These findings underscore the need for disaggregated data, culturally tailored interventions and precision approaches in prevention and treatment to reduce disparities within the diverse Black population diagnosed with breast cancer globally. Funding: Jovanka Ravix reported receiving grants from the National Institutes of HealthNIMHDF31MD020275. Sophia George was funded by the National Institute on Minority Health and Health Disparities (L60MD014321), Chan Zuckerberg Initiative - Ancestry Network DAF2021-240624, Sylvester Comprehensive Cancer COE - IFP. Research reported in this publication was performed in part at the Biostatistics and Bioinformatics Shared Resource of the Sylvester Comprehensive Cancer Center at the University of Miami, RRID: SCR022890, which is supported by the National Cancer Institute of the NIH under award number P30CA240139.