According to the state of TIL, the tumor microenvironment can be divided into three types: (1) immune-inflammatory type: functional CD8+ T densely infiltrated cells; (2) non-infiltrating type: abnormal angiogenesis and immunosuppressive microenvironment to prevent the infiltration of T cells; and (3) immunocompromised type [16]. Here, CD8A is linked to neoplasm.