It is suggested that MCC, as an immunogenic tumor, exerts different strategies of immune escape because it is capable of disturbing cellular immune responses by upregulation of PD-1 and PD-L1 and reducing the human leukocyte antigen (HLA) class I expression, leading to decreased or absent T cell infiltration (Ritter et al., 2017). The gene discussed is PDCD1; the disease is neoplasm.