Eccrine duct carcinoma of the eyelid mimicking meibomian carcinoma: clinicopathological study of a case.

Eccrine duct carcinoma belongs to a group of malignant sweat gland tumors showing de novo eccrine differentiation, but without features of benign adnexal counterparts. They are therefore likely to be confused with visceral adenocarcinomas that have metastasized to the lid. These tumors require important diagnostic considerations when adenocarcinoma is encountered in the lid in the absence of a known primary tumor. We present the case of a 60-year-old man with a nodule in the right upper eyelid that was histopathologically diagnosed as eccrine duct carcinoma of the lid. The differential diagnosis of eccrine carcinomas based on light microscopy, enzyme histochemistry, and immunohistochemistry is discussed, and a list of the various malignant eccrine tumors reported in the lid is presented.