Merkel cells in extraocular sebaceous carcinoma

Abstract

Introduction Mature sebaceous glands do not contain Merkel cells. Neither do sebaceous tumors in the vast majority of cases. Recently, however, it was showed that rare sebaceous adenomas with a carcinoid‐like or labyrinthine pattern can contain intratumoral Merkel cells. Our purpose in this study is to examine for the presence of Merkel cells in extraocular sebaceous carcinomas. Methods Nineteen cases of extraocular sebaceous carcinoma were retrospectively studied with cytokeratin 20. Results One out of 19 cases (5.3%) contained Merkel cells in the basal layers of the tumoral nests of a sebaceous carcinoma from the cheek of a 76‐year‐old woman. Conclusions Merkel cells are rarely evident in extraocular sebaceous carcinoma, and therefore, their evidence does not exclude this diagnosis.

Extraocular cutaneous sebaceous carcinoma in a patient with Muir-Torre syndrome: special emphasis on histologic and dermoscopic features

“…This is probably due to the fact that the we have observed a moderately differentiated CSC and not a well-differentiated one, as in the case series reported by Misago et al (2). In our case, the staining for CK20 was negative within the tumor, confirming the data of the Literature that extraocular CSC do not contain Merkel cells (11).…”