For example, there are multiple studies to explore the immune biomarkers at baseline from peripheral blood samples or biopsied tumor samples to stratify the likely responsible patients to immunotherapy, including tumor mutation burden, circulating tumor DNA, tumor infiltrating lymphocytes, PD-L1 expression in the tumor, etc. Currently, it is unclear if these markers would have predicative value in the immunotherapy of BTCs and it remains an important topic to be illuminated. Here, CD274 is linked to neoplasm.