Serosal overturning assisted endoscopic full‐thickness mucosal resection was performed on the extraneous giant masses at the esophagogastric junction without complications.
It is difficult to perform endoscopic resection of masses at the gastroesophageal junction (GEJ). In particular, the extraneous giant masses surrounding the extraneous giant masses is infrequent. As one of the technologies of endoscopic resection, endoscopic full‐thickness resection (EFTR) is generally applicable to the submucosal tumor of stomach, duodenum and colorectal that originate from the musculus propria and protrude to subserous or partial growth outside the luminal layer. Successful endoscopic repair of perforation is crucial in avoiding the need for surgical repair and preventing postoperative peritonitis, making it a key aspect of EFTR treatment. We report a 56‐year‐old woman who was admitted to our department complaining of 5‐year history of masses of esophagogastric junction and 2‐month history of feeling of gastric distension. Gastroscopy showed a 4 cm submucosal mass near the fundus of the stomach from the cardia. Computed tomography scan revealed submucosal lesions in esophagogastric junction, which was exogenous. We successfully performed Serosal overturning assisted endoscopic full‐thickness mucosal resection on the extraneous giant masses at the esophagogastric junction without complications. The clinical symptoms were significantly improved within postoperative 1 month. There was no recurrence 8 months after the operation. Serosal overturning assisted EFTR is possibly an effective and minimally invasive method of extraneous giant masses at the esophagogastric junction.