Ectopic ampulla of vater in D4 with adenosquamous carcinoma: case report and literature review

Abstract Ampulla of Vater (AOV) is typically located in the second part of the duodenum. There are few reported cases of ectopic AOV over the line extending from the pylorus of the stomach down to the distal part of the duodenum. However, to the best of our knowledge, there are only five cases reported in the English literature of an ectopic AOV in the fourth part of the duodenum, with only one of them having adenocarcinoma of the ampulla. Hereby,