ELF3 and cholangiocarcinoma: Inactivating mutations in ELF3 occur in ~6% of cholangiocarcinomas [26,27] and gallbladder cancers [28,29], and in ~10% of ampullary cancers [30,31], which arise from the Ampulla of Vater, the nipple-like projection into the duodenum into which the pancreatic and bile ducts open.