Cytological, histopathological and immunohistochemical features of merkel cell carcinoma- A case report

Abstract

Merkel cell carcinoma (MCC) is a rare, potentially aggressive primary cutaneous neuroendocrine carcinoma. MCC commonly occurs on sun-exposed skin in fair-skinned elderly individuals. It usually presents as a banal-appearing lesion, and the diagnosis is rarely suspected at the time of biopsy. We describe the cytomorphologic, histopathological, and immunohistochemical characteristics of MCC in a 76-year-old male patient presenting with rapidly evolving large red raised lesion over cheek for 1 month. Cytohistopathological evaluation suggested MCC. Immunohistochemistry revealed that the tumor cells were negative for leukocyte common antigen, S-100 protein, HMB45, and cytokeratin 20 and positive for neuron specific enolase. Because of the documented aggressiveness and rising incidence, early diagnosis of this rare tumor is necessary for the management of MCC.

Keywords

• CK 20 negative
• cutaneous neuroendocrine tumor
• Merkel cell carcinoma