CTLA4 and lung cancer: However, the effectiveness of concurrent therapy of radiotherapy with ICI is not fully established yet, except in some clinical trials showing that irradiation followed by anti-cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) antibody (Ab) treatment in lung cancer resulted in a promising synergistic clinical effect7, and that anti-PD-L1 therapy with chemo-radiation improved the PFS and OS in patients with non-small-cell lung cancer (NSCLC)8,9.