Comparative accuracy of sonography, mammography and the BI-RADS characterization of breast masses among adult women at Mulago Hospital, Uganda

Breast cancer is common among Ugandan women and mortality rate is significantly high. Uganda, like many low-income countries, has no national regular mammography screening programme, a gold standard in breast cancer imaging. Breast ultrasound and Breast Imaging Reporting and Data System (BI-RADS) classification is thus being promoted as a supplemental evaluation tool for breast masses. However, studies on the comparative accuracy of breast sonography, mammography and BI-RADS from low-income settings are limited. This study aimed to determine the accuracy of breast ultrasound, mammography and BI-RADS classification against histology in the evaluation of breast masses among adult women. This was a cross-sectional study conducted at Mulago National Referral Hospital involving women with breast masses. The women underwent breast ultrasound, mammography and needle biopsy for histological analysis. The breast lesions were also evaluated against the BI-RADS characterization criteria. Overall, 212 breast masses were evaluated and included in the analysis. Of these, 50% (106) were benign and 50% (106) were malignant. The sensitivity for ultrasound and mammography separately was 68.5% and 72.5% respectively. The sensitivity for ultrasound and mammography combined was 85%. BI-RADS 5 category had the highest sensitivity at 59.9% while the highest specificity was noted among BI-RADS 3 and 5 at 100%. The highest accuracy was noted in the BI-RADS 5 category at 79.9%. Findings from this study demonstrate that combining ultrasound and mammography could have a higher sensitivity and diagnostic accuracy than when these imaging modalities are used independently. In addition, the BI-RADS reporting classification has an optimum positive predictive value and should be promoted to standardize breast imaging reporting.