Microcystic adnexal carcinoma of the orbit mimicking pagetoid sebaceous gland carcinoma.

Microcystic adnexal carcinoma (MAC) is a rare malignancy of sweat glands that has been reported most often on the face in the form of a cutaneous lesion, with the potential for deeper invasion. The synonyms of MAC include sclerosing sweat duct carcinoma, syringomatous carcinoma, and malignant syringoma. Clinically, MAC in the periocular area has been misdiagnosed as basal cell carcinoma, squamous cell carcinoma, or even chalazia. We report a case of MAC presenting clinically as sebaceous gland carcinoma with pagetoid spread for the first time in literature.