Another study that classified melanoma tumors based on T cell infiltration and PD-L1 expression demonstrated that 38% were type I cancers (PD-L1+TIL+), 41% were type II cancers (PD-L1−TIL−), 1% were type III cancers (PD-L1+TIL−), and 20% were type IV cancers (PD-L1− TIL+) [19]. Here, CD274 is linked to cancer.