Among these drugs, histories of proton pump inhibitor (PPI) use and antibiotic use were associated with poorer outcomes in patients with NSCLC who were treated with ICI monotherapy but not in those treated with cytotoxic chemotherapy.19,20,21,22,23 We thus aimed to clarify the association of concurrent medication history with treatment outcomes in patients with NSCLC with a high PD-L1 TPS treated with ICI with or without chemotherapy, and to determine whether these clinical histories could serve as biomarkers for appropriate treatment selection. The gene discussed is CD274; the disease is non-small cell lung carcinoma.