A case of cystic dermal duct tumor corresponding to poroid hidradenoma.

A case of dermal duct tumor on the back of a 61-year-old male, representing a cystic lesion, is reported. Such cystic dermal duct tumors seem to be considered poroid hidradenomas according to the recently suggested classification of poromas. Poroid hidradenoma is rarely mentioned in the literature, and no description of its clinical features has yet been published. Carcinoembryonic antigen (CEA) immunostaining was positive in the tumor cells adjacent to the cystic space. We suppose that these CEA-positive cells were associated with cyst formation in our case.