Giavina-Bianchi M. et al. [25] highlighted a very important concept concerning PD-L1 immunoexpression in the metastatic setting by studying 50 melanoma metastasis samples from 46 patients on which they performed immunohistochemical reactions with the E1L3N (R) clone (Cell Signaling Technology, Danvers, Massachusetts, United States). This evidence concerns the gene CD274 and melanoma.