Abstract P5-08-16: Breast cancer in the Bahamas: Revisiting the adequacy of national screening guidelines

Abstract

Abstract Background: The Bahamas is an island nation shown to have a high incidence of early onset breast cancer. In addition, recent research has revealed that the Bahamian population has a high prevalence of a founder mutation to the BRCA1 gene. Despite the population differences between the Bahamas and the United States, the screening guidelines for breast cancer in the Bahamas reflect those of the United States. This study provides data that suggests that the current breast cancer screening guidelines in the Bahamas do not capture cases in the age groups most at risk and are in need of revision. Methods: We performed a retrospective review of all cases submitted to the Princess Margaret Hospital cancer registry from 1998-2012. We divided the patients into 10 year age cohorts and determined the frequency of breast cancer in each group. For comparison, data for the United States was obtained using the Surveillance, Epidemiology, and End Results (SEER) 18 registries, including all cases of breast cancer from 1998-2012 further stratified into age groups and ethnicity. Results: The average age of diagnosis of breast cancer in the Bahamas from 1998-2012 was 54 years, compared to an average age of diagnosis in the United States overall population of 61 years and among the black American ethnicity, 58 years (2008-2012 data). The age group with the highest percentage of incidence in the Bahamas is the 40-49 age group consisting of 27% of those diagnosed from 1998-2012. During the same time period, the age group with the highest incidence of breast cancer in the United States was the 50-59 age group in the overall population (24.8%), as well as in the black population (26.7%). By beginning screening at age 40, according to screening guidelines during the study period, the United States was able to capture 95.3% of breast cancer cases in the overall population and 92.8% of breast cancer cases in the black population. Using similar guidelines, the Bahamas captured only 83.6% of breast cancer cases. For comparison, if screening began at age 30 in the Bahamas during the study period, 97% of breast cancer cases would have been captured. Conclusions: The data in this study demonstrates significant differences in the incidence of breast cancer between age group cohorts in the population of the Bahamas compared to the population of the United States. Furthermore, it suggests that the screening guidelines in place in the Bahamas may be insufficient at capturing an adequate percentage of the population at risk for breast cancer. A significant increase in capture of those with breast cancer in the Bahamas may be achieved by reducing the age to begin screening below the age of 40. Citation Format: Deleveaux S, Curling D, Francis W. Breast cancer in the Bahamas: Revisiting the adequacy of national screening guidelines [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-08-16.