Microcystic adnexal carcinoma of the breast: a very rare breast skin tumor.

Background: Microcystic adnexal carcinoma is a rare, slowly progressing, malignant tumor of sweat gland origin.

Objective: A case of microcystic adnexal carcinoma of the breast with a history of 20 years is presented.

Methods: On initial examination, the ulcerative cutaneous mass was fixed to the underlying breast tissue and chest wall.