Updated review of the pathogenesis and management of Merkel cell carcinoma

Merkel cell carcinoma is a rare, aggressive, malignant cutaneous tumor of the elderly or immunosuppressed individuals that usually appears on sun-exposed areas of the body. Its pathogenesis is still debated, and, currently, no standardized treatment exists. OBJECTIVE: To provide a current updated review of the most relevant data concerning the pathogenesis and management of Merkel cell carcinoma. METHODS: Using relevant MeSH terms, we performed a review of the literature on these subjects from 1980 to June 2009. RESULTS AND CONCLUSION: The current management of Merkel cell carcinoma is based on surgical excision as the majority of patients present with localized disease, whereas up to 30% have regional lymph node metastases. In these cases, the best outcome is achieved with multidisciplinary management that includes radiotherapy. Chemotherapy is part of the treatment in advanced cases and is mandatory for distant metastatis. Given that a recent work showed the presence of a previously unknown polyomavirus, which the authors called Merkel cell polyomavirus, the therapeutical approach to Merkel cell carcinoma could be reconsidered in the future.