Complete response with neoadjuvant avelumab in Merkel cell carcinoma - A case report.

Merkel cell carcinoma (MCC) is a rare but aggressive neuroendocrine skin malignancy. We report here a case of localized MCC achieving pathologic complete response upon treatment with avelumab in the neoadjuvant setting. Preclinical and clinical studies have revealed a close relationship between MCC and the immune system, thus supporting a role for PD-1/PD-L1 inhibitors in MCC. This neoadjuvant use of PD-1/PD-L1 inhibitors can avoid potentially disfiguring surgery in MCC. As the incidence of MCC is rising, clinical trials are needed to evaluate the efficacy and safety of immunotherapy in resectable disease.