CD8A and neoplasm: Recently, some biomarkers of PD-1 inhibitors and PD-L1 inhibitors efficacy, including high tumor mutational load [11, 12], neoantigen [11, 13], increased CD8 positive tumor-infiltrating lymphocytes in the tumor microenvironments [14], increased PD-L1 expression on immune cells [15, 16], and the presence of epidermal growth factor receptor (EGFR) mutation [17], have been reported.