Interestingly, IDH1 mutations and FGFR2 fusions were almost reported in intrahepatic cholangiocarcinoma, while extrahepatic had a higher frequency of KRAS, CDKN2A, and BRCA1 mutations; extrahepatic and gallbladder cancer had higher rates of homologous recombination repair deficiency and HER2 overexpression/amplification. This evidence concerns the gene ERBB2 and gallbladder cancer.