Concurrent Metastatic Merkel Cell Carcinoma and Cutaneous Squamous Cell Carcinoma in the Same Lymph Node.

The coexistence of Merkel cell carcinoma (MCC) and squamous cell carcinoma (SCC) in the same cutaneous lesion is well known. The pathogenesis is believed to be distinct from conventional polyomavirus-related MCC, and it has a more aggressive course. Metastasis of MCC and SCC to the same lymph node is exceedingly rare with only one previously reported case in the English literature. To the best of our knowledge, this is the second case of MCC and SCC with metastasis to the same lymph node. Our case demonstrates the aggressive nature of the combined MCC and SCC in the setting of immunosuppression.