Merkel cell carcinoma: diagnostic and treatment

Merkel cell carcinoma (MCC) is an uncommon neuro-endocrine tumor of the sun -exposed skin predominently observed in white patients in the sixth decade of the life. In electron microscopy MCC characteristically contains dense c ore secretory granules. This tumor expresser bath epithelial (keratins of l ow molecular weight of the simple epithelial type, epithelial membrane anti gen) and neuro-endocrine markers (neuron-specific enolase, chromogranin A). The analysis of available litterature indicates that MCC has a propensity for involvement of regional lymphatics (12% of patients dt the date of init ial diagnosis and 50 to 60% afterwards) and for metastases to distant sites (20 to 52%). The prognosis of metastatic disease is poor The overall survi val from the diagnosis of metastases is 6 months. The optimal treatment of locoregional stages should include excision and post-operative radiation. T he role of chemotherapy in this tumor is unclear but recent data suggest a high chemosensitivity.