Adenocarcinoma originating in duodenal heterotopic pancreatic tissue: A case report

Abstract

A 65-year-old man was admitted with upper abdominal fullness. Esophagogastroduodenoscopy and upper gastrointestinal radiography showed duodenal stenosis extending from the bulb to the superior duodenal angulus. Contrast-enhanced abdominal computed tomography scan revealed a tumor with delayed enhancement of a thickened duodenal bulb, and histopathological examination of a biopsy specimen showed adenocarcinoma. Based on these findings, we suspected duodenal cancer and performed a subtotal pylorus-preserving pancreaticoduodenectomy. We found an elastic white duodenal mass measuring approximately 3cm in size on macroscopic examination. Histopathological examination of the resected specimen showed a moderately differentiated adenocarcinoma with islets of Langerhans in the submucosal layer and the muscularis propria. Immunohistochemical examination confirmed the diagnosis of adenocarcinoma originating from duodenal heterotopic pancreatic tissue. We report a rare adenocarcinoma originating in duodenal heterotopic pancreatic tissue.