Rare gastric outlet obstruction owing to ectopic pancreas: a case report and literature review.

The ectopic pancreas is often observed in the gastrointestinal tract, and is typically asymptomatic. A 28-year-old woman was referred to our hospital following repeated vomiting after every meal. Following gastroscopy, contrast-enhanced computed tomography (CE-CT), and endoscopic ultrasonography (EUS), she was diagnosed with gastric outlet obstruction, also known as pyloric obstruction, caused by a giant submucosal cystic tumor. The condition was successfully treated with EUS-guided cystic drainage, and she was diagnosed with a cystic tumor originating from the ectopic pancreas. The tumor shrank following EUS-guided cystic drainage, and her obstructive symptoms resolved. In cases with overgrowth of the ectopic pancreas, the differential diagnosis of malignancy is important but challenging. Herein, we report a unique final pathology of this rare case and discuss the findings with a literature review.