Carcinomas arising in fibroadenomas: a report of two cases and a review of the literature.

Carcinomas arising in fibroadenomas are rare. Two such cases are being presented; one is of the ductal variety and the other, lobular. Both cases clearly demonstrate the overall configuration of fibroadenomas with foci of in situ and infiltrating carcinoma, the surrounding breast tissue being devoid of malignant changes. The diagnosis was clinically unsuspected in both cases and in only one of them was it suspected at the time of gross pathological examination. The intent of this presentation is to increase general awareness as to the existence of carcinomas arising in fibroadenomas and also to actively discourage the practice of rendering gross pathological diagnoses of fibroadenomas at table diagnosis, however innocuous these neoplasms may appear to be, without microscopic examination by frozen sections.