In MCC tumors, CD8 T cell and other immune cell infiltration is usually poor, and those cases with better infiltration positively correlate with patient outcomes (Sihto et al., 2012; Lipson et al., 2013; Wheat et al., 2014; Feldmeyer et al., 2016; Miller et al., 2017). The gene discussed is CD8A; the disease is Merkel cell skin cancer.