Preserved mucosa unroofing facilitated closure of a large gastric defect after endoscopic full-thickness resection.

A 58-year-old woman was found to have a submucosal bulging lesion in the anterior wall of the gastric fundus during a screening esophagogastroscopy. Endosonographic evaluation revealed it to be a 3.1×2.5cm, hypoechoic mass originating from muscularis propria (MP). Endoscopic full-thickness resection (EFR) was attempted. After submucosal injection, a four-fifth circumferential mucosal incision was made around the lesion. Submucosal dissection was performed to unroof the overlying mucosa, which was preserved via the remaining one-fifth circumferential mucosal edge. Thus a mucosal flap was created and turned aside to expose the mass. En bloc resection of the lesion resulted in a 3.5*3.0cm full-thickness defect . The mucosal flap was flipped back and the defect was almost fully covered. Therefore, closure of the defect was accomplished by simply clipping the two edges of the initially incised mucosa. The patient was discharged 2 days later without discomfort. Histopathology confirmed a gastrointestinal stromal tumor (GIST), prognostic group 1.