Duodenal Brunner's gland hyperplasia (BGH) is a therapeutic target when complications such as bleeding or gastrointestinal obstruction occur or when malignancy cannot be ruled out. Herein, we present a case of large BGH treated with endoscopic mucosal resection (EMR).

An 83-year-old woman presented at our hospital with dizziness. Blood tests revealed severe anemia, esophagogastroduodenoscopy showed a 6.5 cm lesion protruding from the anterior wall of the duodenal bulb, and biopsy revealed the presence of glandular epithelium. Endoscopic ultrasonography (EUS) demonstrated relatively high echogenicity with a cystic component. The muscularis propria was slightly elevated at the base of the lesion. EMR was performed without complications. The formalin-fixed lesion size was 6 cm × 3.5 cm × 3 cm, showing nodular proliferation of non-dysplastic Brunner's glands compartmentalized by fibrous septa, confirming the diagnosis of BGH. Reports of EMR or hot snare polypectomy are rare for duodenal BGH > 6 cm. In this case, the choice of EMR was made by obtaining information on the base of the lesion as well as on the internal characteristics through EUS.

Large duodenal lesions with good endoscopic maneuverability and no evident muscular layer involvement on EUS may be resectable via EMR.

With the development and application of endoscopic technology, most pedunculated polyps can be absolutely resected with a complete specimen by hot snare polypectomy (HSP). Brunner's gland hamartoma (BGH) is a rare benign small bowel tumor. The majority of BGH measuring about 2 cm in diameter, rarely larger than 5 cm. Most patients are asymptomatic, some may present with gastrointestinal hemorrhage or intestinal obstruction. Symptomatic larger lesions leading to bleeding or obstruction should be excised either endoscopically or surgically. Whether it is safe and effective that removing a BGH measuring about 7 cm by HSP is not known.

Here, we reported a rare case of a proximal duodenum pedunculated mass measuring about 7 cm which was responsible for the patient's severe anemia. we treated it as a pedunculated polyp. After being pretreated the stalk with an endoloop which was placed around the base of the mass to prevent post-polypectomy bleeding (PPB), the pedunculated BGH was removed by HSP completely. The stalk of the mass was negative. We achieved a curative resection.

It is a safe and effective for our patient to treat the pedunculated BGH measuring about 7 cm as a pedunculated polyp and remove it by HSP. And future prospective studies in larger cohorts are needed to confirm it.

Brunner's gland hamartoma, also called hyperplasia, adenoma, and Brunneroma, is an extremely rare benign proliferative lesion of Brunner's glands in the duodenum. While being mostly small and asymptomatic, they can result in gastrointestinal bleeding and obstruction. We report the case of a 54-year-old man presenting with melena and severe anemia requiring blood transfusion. CT scans showed a large mass of 8 cm in diameter, presumably arising in the duodenum. Endoscopic biopsies were not conclusive. As we were unable to determine the nature of the mass preoperatively and due to the severe symptoms, its size, and the uncertain malignant potential, a classic Whipple procedure was performed. The resected specimen showed extensive proliferation of Brunner's glands without signs of malignancy.

The incidence of polypoidal tumors in the duodenum is scarce and Brunner's gland tumors represent 11% of these proliferations. Brunner's gland polypoid hamartoma or adenoma is a highly infrequent benign polypoid proliferation of Brunner's glands that is usually asymptomatic, although gastrointestinal bleeding or intestinal obstruction may sometimes occur. We present the case of a woman with an incidental diagnosis of duodenal polypoid hamartoma. The lesion was resected with polypectomy loop and at 48 h, the patient presented gastrointestinal bleeding as a complication. We describe the endoscopic treatment of the lesion and this complication.