Kervarrec T, et al. - The viral status of combined Merkel cell carcinoma (MCC), which was an aggressive neuroendocrine carcinoma of the skin was investigated via a multimodal approach. In contrast with conventional MCC, combined MCC exhibited a variation in earlier American Joint Committee on Cancer [AJCC] stage, increased the risk of recurrence and death, decreased CD8 infiltrates, more frequent thyroid transcription factor 1 [TTF1] positivity, abnormal p53 expression and frequent lack of large T antigen expression. Findings reported that one-half of the combined MCC cases were positive for Merkel cell polyomavirus (MCPyV) in the neuroendocrine component, revealed via the molecular procedure. In 5/8 combined MCC cases, beta papillomaviruses were identified and in 9/12 conventional MCC cases. Similar routes of carcinogenesis for combined and conventional MCC were illustrated through the identification of MCPyV DNA in half of the combined MCC cases.