Merkel Cell Carcinoma: Diagnostic and Therapeutic Workup from a Head and Neck Surgeon Perspective

Merkel cell carcinomas (MCC) are highly aggressive skin malignancies, resulting in death of more than one-third of patients with increasing incidences over the past decades. The carcinogenesis is associated with Merkel cell polyomavirus (MCPyV) infection and/or ultraviolet-induced DNA mutations. Diagnosis is made by histology and specific immunohistochemical stains. Among them, cytokeratin 20 (CK20) expression represents indeed the most important marker. The treatment consists of either wide local excision to achieve clear margins accompanied by nodal dissection or radiation therapy. In advanced stage diseases, survival rates still remain low, but immunotherapy with PD-L1 and PD-1 inhibitors are promising. The increasing incidence, the rapidly and aggressive clinical course as well as some unsolved diagnostic and therapeutic challenges underline the need for a better understanding of MCC. Therefore, the aim of this short review was to present an overview of the current literature regarding diagnosis and treatment of MCC patients.