Metastatic Merkel cell carcinoma of unknown origin

case report

Abstract

Merkel cell carcinoma is a rare skin tumor of neuroendocrine origin, high metastatic potential and poor prognosis. Usually, manifests itself in men as firm and fast growing nodular mass, appearing most frequently in sun-exposed areas, such as head and neck. The low incidence of disease and its nonspecific clinical features difficult early diagnosis, which needs to be supported by a careful immunohistochemical study. The high recurrence rates and the high incidence of distant metastases confirm the tumor aggressiveness, which requires multimodal treatment with surgery, chemotherapy and radiotherapy for the majority of affected patients. Strict compliance must be maintained, since the recurrence of the disease occurs in 6 to 12 months after initial diagnosis. Carcinoma metastatic Merkel cell of unknown origin significantly increases the diagnostic and therapeutic challenge. Here we present a case of Merkel cell carcinoma in the right axilla of a 55 years woman with unknown primary site.