Neuroendocrine carcinoma of the skin--an updated review

Primary neuroendocrine carcinoma of the skin, or Merkel Cell carcinoma (MCC), is a rare but aggressive tumor. Many recent advances on the morphology, immunophenotype, and pathogenesis have come to light in recent years. This review highlights the clinical features, varying histologies, histogenesis, advances in molecular pathology, prognosis, and current management of MCC. It also aims to aid in the differential diagnosis, with an emphasis on neuroendocrine tumors, and approach to the diagnosis of MCC with the use of immunohistochemistry and molecular studies.