PDCD1 and neoplasm: In recent years, advances in the treatment of NSCLC have been substantial and promising with the effective application of immunotherapies, including anti-programmed cell death 1 ligand (PD-L1) and anti-programmed cell death 1 (PD-1) antibodies (nivolumab, atezolizumab and pembrolizumab), in selected populations of advanced NSCLC with high tumor mutation burden (TMB) or elevated pretreatment PD-L1 expression [2].