IDH2 and intrahepatic cholangiocarcinoma: Mutations of dehydrogenase (IDH1, IDH2), fibroblast growth factor receptor (FGFR1, FGFR2, FGFR3), Eph receptor 2 (EPHA2) and BAP1 (genes involved in chromatin remodeling) were reported to present in intrahepatic cholangiocarcinoma, while ARID1B, ELF3, PBRM1, cAMP dependent protein kinase (PRKACA) gene mutations were implicated in the distal and perihilar subtypes subtype [50].