Laparoscopic Local Resection via Duodenotomy for Cystic Heterotopic Pancreas Involving the Gastroduodenal Junction: A...

Heterotopic pancreas is an uncommon condition characterized by the pancreatic tissue lacking anatomical continuity with the main pancreas. Cystic changes are rare, and lesions involving the gastroduodenal junction present diagnostic and technical challenges because the exact site of origin may be difficult to determine.

A 53-year-old man presented with epigastric fullness. Endoscopy and imaging revealed food retention in the stomach and a 4.5-cm cystic submucosal lesion in the duodenal bulb. Endoscopic ultrasonography revealed a predominantly anechoic cystic lesion. However, the layer of origin could not be determined. CT and MRI revealed no solid components or continuity with the pancreas. Although no definitive malignant features were observed, duplication cysts or mesenchymal tumors could not be excluded. Laparoscopic surgery was performed for both diagnostic and therapeutic purposes. Intraoperatively, a lesion was found near the pyloric ring that protruded into the duodenum; however, this reduction was unsuccessful. A longitudinal duodenotomy was performed to deliver the tumor into the abdominal cavity, and the lesion was resected, including its base. The defect was closed transversely using a 2-layer Albert-Lembert closure, and intraoperative endoscopy confirmed luminal patency. Histopathological examination revealed a Heinrich type II heterotopic pancreas with retention cyst formation. Pathological mapping demonstrated that the ductal opening was identified on the duodenal mucosal side, and no heterotopic pancreatic tissue was exposed at the resection margin. No dysplasia, pancreatic intraepithelial neoplasia, or malignant transformation was observed. Both the gastric and duodenal mucosa were identified on the lesion surface, indicating involvement of the gastroduodenal junction. The postoperative course was uneventful.

A cystic heterotopic pancreas involving the gastroduodenal junction may preclude precise preoperative identification of its origin. When reduction is not feasible, duodenotomy allows direct assessment of the lesion base and facilitates appropriate resection while avoiding distal gastrectomy and maintaining gastric outlet patency.