In conclusion, MDM2 amplification in large-duct iCCAs is more common than presently considered, and it may represent a unique biliary carcinogenetic process in which KRAS and TP53 mutations are less frequent.
The most common alterations were TP53, KRAS, and CDKN2A in gallbladder carcinoma; TP53, KRAS, PIK3CA, and BRAF in intrahepatic cholangiocarcinoma; and TP53 and SMAD4 in extrahepatic cholangiocarcinoma.