Microcystic Adnexal Carcinoma: A Case Showing Eccrine Duct Differentiation

Abstract
Microcystic adnexal carcinoma (MAC) is a cutaneous neoplasm comprised of pilar and sweat duct structures. Characteristically, the ductal structures manifest immunoreactivity for carcinoembryonic antigen (CEA) on immunostaining. The case of MAC discussed here shows strictly sweat duct differentiation. Using a monoclonal antibody to salivary mucin (CF-1) that is specific for eccrine duct, we identify the neoplastic structures to be of eccrine sweat duct histogenesis.