Purpose: To retrospectively analyze the positive predictive values (PPVs) of the breast lesions classified as categories 4 and 5 by using Breast Imaging reporting and Date System (BI-RADS) ultrasonography (US).
Materials and Methods: Between January 2013 and December 2013, the 1815 breast lesions of 1408 patients were reported BI-RADS US category 4 and 5. We reviewed the frequency, pathologic or clinical course.
The positive predictive value (PPV)s for category 4a, 4b, 4c and 5 were evaluated.
Results: Among the 1815 lesions, the 1282 lesions were pathologically confirmed as benign lesions and the 491 lesions were pathologically confirmed as malignant lesions. The 42 lesions were not pathologically confirmed.
The PPV for category 4 was 17.4% and the PPVs for subcategory 4a, 4b and 4c were 9.7%, 52.1% and 81.5%. And the PPV for category 5 was 94.9%.
Conclusion: In our hospital, the PPVs for BI-RADS US category 4a, 4b, 4c and 5 were nearly within the reference range of BI-RADS US, so it was appropriately subcategorized.