In the trials of PD-1/L1 inhibitor monotherapy of non-small cell lung cancer, such as KEYNOTE-042 and IMpower110, patients with high PD-L1 expression (≥50%) were likely to have prolonged survival (Mok et al., 2019; Herbst et al., 2020). Here, PDCD1 is linked to non-small cell lung carcinoma.