PDCD1 and non-small cell lung carcinoma: Monoclonal antibodies targeting the cytotoxic T-lymphocyte antigen-4 (CTLA-4) and programmed cell death 1 (PD-1/PD-L1) checkpoint pathways are used in the clinic to treat several solid tumors such as metastatic melanoma and non-small cell lung carcinoma (12–16).