Positive Predictive Rate of Breast Imaging-Reporting  and Data System (BI-RADS) Category 4 Lesions For Breast Cancer Taking Histopathology as Gold Standard

Objective: To determine positive predictive rate of Breast imaging-reporting and data system (BI-RADS) category 4 and its sub-categories for breast cancer taking histopathology as gold standard. Study Design: Cross sectional validation study. Place and Duration of Study: Department of Radiology, Pakistan Institute of Medical Sciences, Islamabad Pakistan, from Sep to Nov 2020. Methodology: 60 female patients who were diagnosed as Breast imaging-reporting and data system (BI-RADS) category 4 lesions on mammography were included in the study and afterwards followed for biopsy report. Data was collected and analyzed using SPSSv25. Results: Patient’s mean age was 50.6±9.7yrs. Among sixty patients with BIRADS 4, 13(21.7%) had BIRADS 4A, 22(36.7%) had BIRADS 4B and 25(41.7%) had 4C. Positive predictive value for BIRADS 4 was 68.33%, 4A was 15.3%, 4B was 72.7% and for 4C was 92%. Sensitivity & Specificity of BIRADS 4A being benign and BIRADS 4B, & 4C being malignant is 91.49% and 69.23% respectively. Overall, diagnostic accuracy of BIRADS 4B & 4C classification was found to be 83.33%. Conclusion: Sub-categorization of Breast imaging-reporting and data system (BI-RADS) category 4 is not routinely practiced, however results of current study conclude that it helps to stratify the associated risk of malignancy and update the level of concern to referring physician and pathologist.