The aims of this study were to evaluate and compare the protein expression and localization of FAP in surgically resected CCA, primary intrahepatic and extrahepatic metastatic HCC, hepatocellular adenoma (HCA), and focal nodular hyperplasia (FNH), and to identify any association between CCA clinical or pathologic features and FAP expression. The gene discussed is FAP; the disease is cholangiocarcinoma.