Merkel Cell Carcinoma

Abstract

Abstract Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine skin cancer characterized by early and frequent metastasis, resulting in a 5‐year disease‐associated mortality rate of more than 40%. Predisposing factors include immune suppression, sun exposure and advanced age. Most MCCs are characterized by a clonal integration of the Merkel cell polyomavirus into the host genome, and virally encoded proteins appear necessary to maintain tumour cell growth. While MCC is still a rare cancer, its incidence is constantly and rapidly rising. Management of the primary tumour stage includes wide local excision, sentinel lymph node biopsy and adjuvant radiation. Management of systemic disease is, however, challenging. Indeed, while the tumour shows high response rates to chemotherapy, these responses are mostly short lived and no therapy regimen has proven survival benefit. Immunotherapy seems promising but clinical studies are needed to confirm its value.