The Accuracy of BI-RADS Classification of Breast Ultrasound as a First-Line Imaging Method

Purpose: The aim was to evaluate the accuracy of BI-RADS categories 3 - 5 in breast ultrasound (US) as the first-line imaging method. Materials and Methods: 5077 examinations of a consecutive, unselected and mixed collective of symptomatic and asymptomatic patients were performed. Of these examinations, 835 cases of BIRADS 3 - 5 could be analyzed. Results: The PPV with respect to a malignant lesion for BI-RADS 3, 4, 5 was 0.03, 0.48, and 0.97, respectively. When BI-RADS 4 and 5 cases are considered to be suspicious, the ratio of benign to malignant findings corresponds to 1:1.8. Analyzing BIRADS 3 - 5 lesions, the sensitivity, specificity and accuracy are 0.92, 0.85, and 0.87, respectively. Conclusion: The data support the feasibility of US for discriminating malignant from benign findings corresponding to the ACR BI-RADS classification without excessively increasing the number of unnecessary biopsies.