PDCD1 and non-small cell lung carcinoma: Recently, the immune checkpoint blockade therapy (ICBT), such as anti-programmed cell death 1 (anti-PD-1) therapy, anti-cytotoxic T-lymphocyte antigen 4 (anti-CTLA-4) therapy and anti-programmed cell death-ligand 1 (anti-PD-L1) therapy, have been shown to make a great breakthrough in the therapeutic strategies against human NSCLC [9–11].