Merkel cell carcinoma from renal transplant recipients are mostly MCPyV-negative and are frequently associated with squamous cell carcinomas or precursors Briefly, patients were mostly male (M/F: 10/5), with a median age at MCC diagnosis of 63 years (range 52-84) and a median delay of 11.5 years (range 1-24 years) between transplantation and MCC diagnosis. In line with the hypothesis that MCPyV-negative tumours may derive from SCC, six patients with MCPyV-negative tumours had a prior history of SCC. [Extracted from the article]