The discovery of cytotoxic T lymphocyte-associated molecule-4 (CTLA-4), programmed death-ligand 1 (PD-1), and programmed cell death receptor-1 ligand (PD-L1) pathways has paved the way for the development of ICI therapy, which has significantly improved the survival in patients with NSCLC without EGFR or ALK alterations. Here, CTLA4 is linked to non-small cell lung carcinoma.