Mutations in FGFR1, FGFR2, IDH1, IDH2, BAP1, and ARID1A are more commonly found in intrahepatic cholangiocarcinoma, while SMAD4 mutations are more commonly seen in extrahepatic cholangiocarcinomas [38,39,40,41,42]. This evidence concerns the gene IDH1 and intrahepatic cholangiocarcinoma.