Abstract
A 46-year-old woman with general fatigue was identified with anemia in a private clinic. She was then referred to our hospital for further evaluation. A detailed examination revealed a pediculate tumor about 40 mm in diameter from the duodenal bulb. Endoscopic mucosal resection (EMR) was difficult because of the tumor dimensions, so a polypectomy was performed by laparotomy. Histological examinations diagnosed it a Brunner's gland hamartoma. In the case of upper gastrointestinal bleeding, the possibility of Brunner's gland hamartoma should be considered in the differential diagnosis.