Primary mucinous carcinoma.

Primary mucinous carcinoma of the skin is a rare entity. It usually presents as a painless nodule, cyst, or ulcer in the head and neck region (especially the eyelid). These tumors have a low metastatic potential but tend to recur locally. Histologically, groups of light- and dark-staining epithelial cells form cords, nests, and ducts separated by clear areas representing sialomucin. Due to tumor continuity and a low rate of lymphatic or hematologic spread, Mohs micrographic surgery appears to be an effective treatment. Herein, two cases of primary mucinous carcinoma are presented.