[(Gynecomastia as precancerous lesion: aspiration biopsy cytology and its histology)]

In 19 of 39 patients suffering from gynecomastia, between 1967 and 1979 aspiration biopsy cytology and surgery was performed by the author. Atypia and precancerous lesions accompanied by an advanced stage of epithelial proliferation were found in two cases, in two other ones, in addition to the above mentioned lesions, breast cancer was discovered. The myoepithelial elements observed cytologically and histologically are important pathognomonic signs in theses patients. In spite of the few cases, the precancerous nature of gynecomastia, primarily in its proliferative forms, manifests itself.