PDCD1 and non-small cell lung carcinoma: Aiming at Programmed cell death-1 (PD-1) and Programmed cell death-ligand 1(PD-L1) mab has been widely used in the clinical treatment of non-small cell lung cancer (NSCLC), but tumor heterogeneity and the complexity of immune microenvironment result in less than 20% of patients benefiting from ICI therapy [4].