CD274 and neoplasm: However, the biomarkers that were previously well‐established in ICI monotherapy have proven ineffective in informing treatment benefit from ICI‐chemo.[1, 2, 3, 4, 5] For instance, tissue tumor mutation burden (TMB) and programmed death‐ligand 1 (PD‐L1) expression have shown limited efficacy in predicting a superior survival benefit from ICI‐chemo over chemotherapy alone in the first‐line setting.[1, 2, 3, 4, 5] Moreover, most studies investigating biomarkers for ICIs did not include a control group.