CD274 and neoplasm: Currently, deficient mismatch repair/microsatellite instability-high (dMMR/MSI-H), tumor mutation burden-high (TMB-H) and PD-L1 expression have been widely studied as biomarkers related to response to immunotherapy in solid tumors (15–17), but the evidence in CCA is insufficient (11, 12, 14, 18, 19).