Breast biopsy evaluation by paraffin-block radiography.

The presence of occult breast carcinoma in breast biopsy specimens originally interpreted pathologically as benign has been reported in up to 2.4% of cases. Paraffin-block radiography of 658 blocks from 119 breast biopsies obtained prior to the use of mammography and initially interpreted as benign was performed to determine the frequency and relevance of "significant" calcifications. Of all cases 87.4% demonstrated some calcifications within the breast tissue; 19.3% contained calcifications considered significant. Step sections of the original blocks containing significant calcifications did not demonstrate malignant neoplasms.