Regarding genomic alterations, CCA falls midway in the cancer mutational spectrum, and gene mutations are associated with poor prognosis (45, 46), for example, IDH, EPHA2, BRAF, BAP1 mutations, and FGFR2 fusions in intrahepatic CCA, whereas extrahepatic tumors specifically show PRKACA, PRKACB, ELF3, and ARID1B mutations. This evidence concerns the gene ELF3 and cholangiocarcinoma.