CD8A and neoplasm: Phenotypic differences in T cell infiltration within the TME can be summarized into three categories: the “immune-inflamed/hot” phenotype, in which CD8+ T cells infiltrate the tumor; the “immune-excluded” phenotype, in which infiltrating CD8+ T cells accumulate in the tumor stroma and the “immune-desert/cold” phenotype, in which CD8+ T cells are low or absent from the tumor and the stroma [98,99].