Immunohistochemistry staining of CCA tumors has demonstrated that 7.3% of intrahepatic CCA and 5.2% of perihilar or distal CCA are PD-L1 positive, indicating that PD-L1 is relatively poorly expressed in CCA compared with other cancers such as melanoma or colon cancer. Here, CD274 is linked to malignant colon neoplasm.