BI-RADS Descriptors for Mammographically Detected Microcalcifications Verified by Histopathology After Needle-Localized Open Breast Biopsy

OBJECTIVE: The objective of our study was to retrospectively determine the positive predictive value of each descriptor and of combined descriptors for microcalcifications to predict the risk of malignancy as well as the appropriate final assessment category. MATERIALS AND METHODS: A total of 308 needle-localized open breast biopsies for mammographically detected microcalcifications were performed in 295 women (age range, 33-71 years; mean age, 52 years) during 7 years. Thirteen patients had bilateral microcalcifications that were studied separately. Two breast radiologists retrospectively reviewed the microcalcifications with regard to their morphology, distribution, and extent and to associated findings and final assessment category, after which they categorized them into nine combined descriptors. Surgical pathology served as the reference standard for malignant lesions and follow-up of at least 12 months served as the reference for benign lesions. The Fisher's exact test, including odds ratios, was used for statistical analysis. RESULTS: Of the 308 needle-localized open breast biopsies, 144 (47%) were malignant and 164 (53%) were benign. For combined descriptors of morphology and distribution, the odds ratios of malignancy regarding the higher probability of malignancy and ductal distribution were as follows: 0 for typically benign morphology or scattered distribution, 93.00 for intermediate concern and regional, 33.53 for intermediate concern and clustered, 5.00 for intermediate concern and ductal, 24.00 for higher probability of malignancy and regional, and 1.13 for higher probability of malignancy and clustered. CONCLUSION: Each descriptor and combined descriptors for microcalcifications and the final assessment category could help to predict the risk of malignancy.