This study is for patients with advanced squamous cell carcinoma of the skin. The purpose of this study is to see if adding a new drug called avelumab to another drug call cetuximab can increase the length of time patients are alive without their cancer getting worse.

This study is for patients that have been diagnosed with Merkle Cell Carcinoma. The investigational drug in this study is pembrolizumab. The purpose of this study is to compare the usual approach of post-surgery observation with or without radiation to using pembrolizumab with or without radiation after surgery. Participants can expect to be on this study for a total of 5 years.