Comparing breast cancer characteristics and outcomes between black U.S.-born patients and black immigrant patients from individual Caribbean islands.

Abstract

e13633 Background: Caribbean-born black immigrants (CBI) represent 57% of all black immigrants in the US; they come mainly from Haiti, Jamaica, Dominican Republic (DR), and Cuba. Breast cancer (BC) is the leading cause of cancer deaths in women living in the Caribbean, however, our previous retrospective cohort of 1131 black women with BC shows that CBI have a better overall survival compared with US-born black (USB). The Caribbean has a majority of African ancestry; nonetheless, different ancestral populations differ in genetic composition, making the Caribbean a distinct population with several health disparities within it. Therefore, we stratified our study by each Caribbean country compared to USB patients with the objective of further studying the difference in BC outcomes between USB patients and CBI. Methods: We identified BC patients through a Safety Net and Private Hospital Tumor Registries. We selected the most populace sites: Haiti, Jamaica, Bahamas, Cuba and DR; and used data from 1,082 patients to estimate hazard rations (HRs) using Cox proportional hazards regression and Kaplan Meier analysis for overall survival; Chi Squared and independent sample t-test to verify associations in categorical variables. Results: The study has 250 Haitian, 89 Jamaican, 43 Bahamian, 38 Dominican, 38 Cuban and 624 USB women. Haitians underwent less surgery (HB 61.2% vs USB 72.9%; P = 0.001) and had less triple negative BC (18% vs USB 27.8%; P = 0.006). Bahamians were the youngest at diagnosis (50.5 years vs. USB 57.6 P < 0.001) and presented at more advanced stages (stage 3/4, 54.3% vs USB 35.3%; P = 0.02). Jamaicans and DR underwent more radiation therapy (43.8%, P = 0.002 and 44.7%, P = 0.028 vs. USB 28%). Jamaican women had a better overall survival compared to USB patients (median of 154.93 months, 95% CI: 114.1-195.5 vs 98.63 months, 95% CI: 76.4-120.8; Log-Rank Mantel Cox P = 0.034). Favorable factors for survival were: radiation therapy in Haitian and USB (aHR = 0.45, 95% 0.27-0.77; P = 0.004); and surgery in USB (aHR = 0.26 (0.19-0.36), p < 0.001), Bahamians (aHR = 0.05 (0.01-0.47), p = 0.008) and Jamaicans (aHR = 0.08 (0.03-0.24), p < 0.001). Conclusions: This study underlines the vast heterogeneity in the Caribbean population and demonstrates that Jamaican immigrants with BC have a higher overall survival compared to USB patients, proposing that genetic and other cancer related factors inherent to country of origin impact survival within Caribbean immigrants and highlighting the need for further studies in this immigrant sub-group.