CD274 and hepatocellular carcinoma: Several studies have shown trends toward patients with HCC with positive programmed death-ligand 1 (PD-L1) expression having a higher response to immune checkpoint inhibition monotherapy.3 15 For BTCs treated with nivolumab, PD-L1 expression was also associated with better PFS and OS.5 In clinical practice, biomarkers based on tumor tissue have some shortcomings, including the difficulty of obtaining enough tumor tissue as well as spatial heterogeneity.