Merkel cell carcinoma is a rare and aggressive neuroendocrine tumor of unknown origin that typically presents in older white and immunocompromised adults. An estimated 2,488 cases are diagnosed in the United States annually (Paulson et al, 2018). The incidence of MCC has risen rapidly during the past few decades, which has been attributed in part to people living longer with increased sun exposure and weakened immune systems, a feature that suggests an infectious origin and warrants further rese...