Abstract
This article highlights the main inducers of cholangiocarcinogenesis. Data are presented on the study of gene mutations, the variations of which depending on the localization of biliary cancer may be different (FGFR2 in intrahepatic PRKACA, PRKACB cholangiocarcinoma in extrahepatic cholangiocarcinoma). Mutations in the KRAS, TP53, ARIAD1A genes are common in extrahepatic bile duct cancer. Epigenetic events such as DNA hypermethylation, histone modifications, chromatin remodeling, and disturbances in miRNA expression are considered. A number of epigenetic features, such as the presence of a TP53 gene mutation with hypermethylation of p14ARF, DAPK, and/or ASC, correlate with a more aggressive course of the disease. The role of the SOX17 gene in the development of drug resistance is highlighted. The study of molecular genetic features of extrahepatic bile duct cancer is an important aspect in understanding the pathogenesis of this type of tumor, reveals new prognostic and diagnostic markers of the disease. It is possible that in the future, as knowledge is accumulated, this will make it possible to individualize approaches to the treatment of this category of patients.