CD8A and non-small cell lung carcinoma: Due to a significant positive correlation between PD-L1 and CD8 infiltrate in NSCLC, we further classified the patients into four subgroups: (1) PD-L1loCD8lo; (2) PD-L1loCD8hi; (3) PD-L1hiCD8lo; (4) PD-L1hiCD8hi.