CTLA4 and non-small cell lung carcinoma: Programmed cell death-1 (PD-1), programmed cell death ligand-1 (PD-L1), and monoclonal antibodies against cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) are the most common ICIs currently used for NSCLC; these ICIs restrict T cell effector activity within tissues or downregulate the amplitude of T cell activation (10).