Abstract
ABSTRACT
A 59‐year‐old man presented with left upper abdominal pain. Contrast‐enhanced computed tomography suggested a duodenal intussusception and a mass with mixed fat and soft‐tissue density extending from the duodenal bulb to the descending duodenum. Esophagogastroduodenoscopy identified a giant pedunculated lesion originating from the posterior wall of the duodenal bulb with a focal depressed area and marked redness. Narrow‐band imaging showed no obvious epithelial neoplastic changes. An upper gastrointestinal series demonstrated an elevated lesion approximately 5 cm in size. Based on these findings, we suspected giant duodenal Brunner's gland hyperplasia. Endoscopic resection was performed under general anesthesia due to the risk of intussusception and potential malignant transformation. En bloc resection was achieved using a scissor‐type endoscopic device with traction, and the specimen was safely retrieved under laparoscopic assistance with gentle compression. Histopathological examination revealed lobulated proliferation of Brunner's glands with fibrous septa and adipose tissue in the submucosa, confirming duodenal Brunner's gland hyperplasia.