Gastric lipoma causing ball-valve syndrome successfully treated by endoscopic submucosal dissection.

Ball-valve syndrome (BVS) is a rare condition characterized by intermittent gastric outlet obstruction caused by a mobile gastric lesion. Large gastric lipomas associated with BVS have traditionally been managed surgically; however, minimally invasive endoscopic treatment may be feasible in selected cases. We report a case of a 52-year-old woman presenting with a 1-month history of postprandial epigastric discomfort and nausea. Contrast-enhanced computed tomography revealed a well-defined, low-attenuation mass extending from the gastric antrum to the duodenal bulb. Esophagogastroduodenoscopy demonstrated a broad-based subepithelial lesion exceeding 50 mm in diameter that repeatedly prolapsed through the pylorus, consistent with BVS. Endoscopic ultrasound showed a homogeneous hyperechoic lesion arising from the submucosa. Based on these imaging findings, a lipoma was strongly suspected, although liposarcoma could not be completely excluded. Therefore, endoscopic submucosal dissection (ESD) was performed as a diagnostic and therapeutic approach. Using a clip-with-line traction method, en bloc resection was successfully achieved without adverse events. The resected specimen measured 103 × 41 × 20 mm, and histopathological examination confirmed a gastric lipoma. The patient's symptoms resolved completely after the procedure, with no recurrence at 1-year follow-up. In conclusion, ESD can be a safe and effective minimally invasive treatment for large gastric lipomas causing BVS, particularly when a confident preoperative diagnosis can be established.