Advances in Merkel cell carcinoma from a pathologist's perspective.

Merkel cell carcinoma (MCC) is a rarely made but potentially devastating diagnosis. While local disease might be cured by surgery and radiotherapy, advanced disease is usually rapidly progressive and fatal. Until very recently, the only approach to metastatic MCC was cytotoxic chemotherapy with results so disappointing that current treatment guidelines discourage its use and recommend clinical trial as a more viable treatment option. Fortunately, recent advances in the understanding of the molecular pathogenesis of this tumour have produced a wide variety of experimental treatments for MCC, some of which are quite promising. The most current information regarding the diagnosis, staging, management of this tumour is briefly presented as well as new insights into the molecular basis of MCC and therapeutic approaches to MCC.