Breast Density Patterns and Their Association with BI-RADS Categories among a Large Cohort of Ghanaian Women

Introduction: Breast cancer remains a major global health challenge, with Africa and other developing countries experiencing its greatest impact. Knowledge of breast density (an independent risk factor) is essential for early breast cancer diagnosis. However, such data is scarce across Africa and absent in Ghana. The aim of this work was to investigate the association between mammographic breast density patterns and BI-RADS assessment categories among women in Ghana. Material and methods: A retrospective cross-sectional study was conducted on 2,108 women who underwent mammography between October 2011 and December 2022. Breast density was visually assessed by radiologists using the American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS). Associations between breast density, age, and BI-RADS assessment categories were analysed using Fisher's Exact Test. Results: Breast density category B (scattered fibroglandular tissue) was most common (44%, n = 935), followed by category A (almost entirely fatty; 39%, n = 821), category C (heterogeneously dense; 16%, n = 397), and category D (extremely dense; 1%, n = 23). More than 50% of all categories received benign diagnoses (BI-RADS 2), while less than 10% recorded negative diagnoses (BI-RADS 1). Higher-density categories demonstrated a greater proportion of suspicious and malignant findings: in category D, 17% were BI-RADS 3, 17% BI-RADS 4, and 13% BI-RADS 5, compared to lower proportions in categories A and B. Confirmed malignancies (BI-RADS 6) were observed across categories A-C (1% each). A significant association was found between breast density and cancer diagnoses (p < 0.05), as well as between age and breast density (p < 0.05). Conclusion: There is a significant association between breast density and BI-RADS assessment categories, with lower breast density observed in older women, a finding consistent with published literature. These results highlight the need for tailored breast cancer screening strategies in Ghana.