CTLA4 and non-small cell lung carcinoma: This article reviews the mechanism of action of programmed death receptor-1 (PD-1)/programmed death ligand-1 (PD-L1) and cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) ICIs, including their clinical applications and related clinical trials, focusing on clinical trials related to ICIs to provide ideas for treatment options for NSCLC patients.