CD8A and melanoma: A significant presence of T cells identified in the tumor microenvironment (TME) generally is associated with a good prognosis.18 In particular, CD8+ TILs are associated with improved RFS and OS for melanoma, which may be closely related to the directly killing effect of CD8+ TILs on tumor cells.30 The TME consists of cancer cells, inflammatory cells, stromal cells, and cytokines, and these components form a complicated immunosuppressive network in cancer, which limits T cell activation and induces T cell dysfunction.