Clinically nonpalpable breast tumors: global critical review and second look on microcalcifications

Over a ten-year period a series of 350 nonpalpable breast lesions were examined to evaluate the positive predictive value of malignancy of the different mammographic findings and the incidence of carcinoma in situ in the different categories. Lesions were separated into opacities and microcalcifications. Surgical biopsy revealed the presence of carcinoma in 190 of 350 lesions with an overall PPV of 54% and a B/M ratio of 0.84. Within opacities, the PPV was 80.2% for spiculate opacities, 53.8% for irregular opacities, 34.7% for opacities with calcifications and 17.4% for parenchymal distortions. As many as 151 of 350 (46%) lesions were shown to be isolated microcalcifications on mammography with an overall PPV of 46% and a B/M ratio of 0.92. 42 of 80 malignant lesions were shown to be ductal carcinomas in situ (50%). According to data of the literature PPV for Le Gal and BI-RADS class 5 was 92% and 86.27%, respectively. Le Gal classification of microcalcifications intends to describe a sign with which a risk of malignancy is associated. In BI-RADS categorization the sign plays a prognostic role and for each class a diagnosticotherapeutic approach is suggested. Therefore a correct BI-RADS categorization can be of support for both radiologists and clinicians in the patient management.