Merkel Cell Carcinoma: Updates on Pathogenesis, Diagnosis, and Management
Purpose of Review
To describe updates on the pathogenesis, diagnosis, and management of Merkel cell carcinoma (MCC).
Sequencing studies revealed that MCCs have either a low mutational burden and integrated Merkel cell polyomavirus (MCPyV), or they have a high number of ultraviolet-associated somatic mutations and no MCPyV. Clinically, prognosis was better for stage III MCC of unknown primary than known primary. Similarly, lack of immunosuppression conferred better prognosis. The immunogenicity of MCC was reflected in high response rates to PD-1/PD-L1 checkpoint inhibitors.
MCC is a rare but aggressive neuroendocrine skin cancer associated with advanced age and immunosuppression. Approximately 80% of MCCs are MCPyV driven, whereas MCPyV-negative tumors have mutations in genes such as p53 and RB1. MCC is highly immunogenic, and recently, the anti-PD-L1 antibody avelumab was approved to treat metastatic MCC. Here, we summarized features of the pathogenesis, diagnosis, and management of MCC.
KeywordsMerkel cell carcinoma Merkel cell polyomavirus Pathogenesis Diagnosis Management
This research was supported by the NIH Intramural Research Program, Center of Cancer Research, National Cancer Institute.
Compliance with Ethical Standards
Conflict of Interest
Dr. Brownell reports work prepared as part of official duties as a US government employee for Intramural Research Program, CCR, NCI, during the conduct of the study.
Jannett Nguyen and Natasha Hill declare that they have no conflict of interest.
Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIH.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
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