CD8A and cancer: Indeed, thanks to the distribution of T CD3+ and T CD8+ lymphocytes in the center of the cancer or at the invasive margin, it could be possible to distinguish four different phenotypes of cancers: (1) the hot ones, with a high infiltration of cells all over the tumor; (2) altered–excluded with the presence of cells only at the invasive margin; (3) altered–immunosuppressed with sparse immune cells within all the tumor; and (4) cold tumors, without infiltration (75).