Clear cell hidradenocarcinoma of the breast: a very rare breast skin tumor.

Hidradenocarcinoma is an uncommon malignant intradermal tumor of sweat gland origin with a predilection for the face and extremities. It is encountered equally in males and females, usually in the second half of life. These tumors tend to be locally aggressive. In our case, the tumor was located relatively superficially but without any apparent connection to the overlying skin. The typical disease course includes local and sometimes multiple recurrences, and some patients develop regional lymph node and distant metastases. These type of tumors in the parenchyma of the breast are extremely rare. We report a case of hidradenocarcinoma in a 77-year-old woman who presented with a palpable inflammatory nodule in the right breast.