Abstract
The patient was a 49-year-old female with a submucosal tumor (12×12 mm) located in the lesser curvature side of the stomach. The diagnosis by endoscopic ultrasound fine-needle aspiration was of a gastrointestinal stromal tumor. Computed tomography and endoscopic ultrasound showed gastrointestinal stromal tumor with an intra-luminal growth type. Endoscopic full-thickness resection was then performed. To achieve good counter traction, enough safety margin, and minimal defect of muscle, full-thickness resection via creating a submucosal tunnel was performed as a new technique. The final histological diagnosis was gastrointestinal stromal tumor with R0 resection.