The histopathology of non-palpable breast lesions detected by clinical mammography.

An histological study of 227 non-palpable breast lesions detected by clinical mammography revealed 64 invasive carcinomas at a mean patient age of 60.5 years. There were 10 carcinomas in situ, mean age 57.2 years. Fibrocystic disease with intraductal epithelial hyperplasia was found in 41 specimens, mean age 54.3 years. Fibrocystic disease without intraductal hyperplasia was found in 57 biopsies, mean age 50.7 years. Histological microcalcifications were found in 113 biopsies, and were considered to be a marker for epithelial proliferation of both benign and malignant kinds. Microcalcifications detectable in histological sections and by mammography differ in size by a factor of 10 or more. This difference has to be considered when comparing histological and mammographic findings.