Intracystic carcinoma of the breast in an elderly man.

An eighty year old man with a mass in the left breast visited our department on October 27, 1980. Examination disclosed a smooth surfaced, round, elastic soft, 3 cm in diameter sized, non-tender mass underneath the left nipple. Mammogram showed a well defined oval opacity and echogram showed a cystic lesion. The mass was punctured and dark brown fluid was aspirated, but there were no malignant cells. The cyst was extirpated and a rice grain sized mass was found in the cyst wall. Histologically, it was diagnosed as non-infiltrating medullary tubular carcinoma. On November 27, 1980, simple mastectomy revealed no histological evidence of a residual cancer.