CTLA4 and non-small cell lung carcinoma: Initially, anti-programmed death-1 (PD-1) antibodies [4,5,6] or anti-programmed death ligand-1 (PD-L1) monotherapy [7,8] was used, but combinations with chemotherapy [9,10,11,12,13] or anti-cytotoxic T-lymphocyte-associated protein-4 (CTLA-4) antibodies [14,15,16] have improved outcome, and have now been approved for the treatment of advanced NSCLC.