Correlation between mammography and the pathology of nonpalpable breast lesions

One hundred consecutive needle localization biopsies were performed for nonpalpable breast lesions discovered on low-dose mammography of asymptomatic women between June, 1984, and August, 1986. Malignant disease was found on 21 biopsies. Four were carcinoma in situ, and 17 were infiltrating carcinomas. Only three of the infiltrating carcinomas had metastasized to regional nodes, as confirmed by subsequent axillary dissection. Two of these metastatic tumors involved two nodes and the third only one. The findings on the remaining 79 biopsies were benign. Forty-eight mammograms were read as "benign"; all (100%) were benign pathologically. Thirty-one mammograms were considered "malignant"; 19 (61%) were malignant pathologically. Only two of the 21 mammograms given "suspicious" interpretations were malignant. Microcalcifications correlated with malignancy only 30% of the time (12/42).