Abstract
A 74-year-old man presented with intestinal obstruction. CT (computed tomography) revealed a 25-mm mass in the proximal jejunum. Double-balloon endoscopy (DBE) identified a smooth, asymmetrically localized mass with oozing and luminal stenosis covered with the mucosa of swollen villi. Small bowel radiography demonstrated jejunal obstruction. Histopathological examination of the resected specimen confirmed moderately differentiated adenocarcinoma arising from ectopic pancreatic tissue of Heinrich type I. Our case suggests that cancer arising from ectopic pancreas should be considered as a candidate diagnosis of a submucosal tumor in the jejunum.