Minimally invasive surgery for submucosal (subepithelial) tumors of the stomach

Figure 1 Endoscopic submucosal tunnel dissection. A: After the mucosa is lifted by submucosal injection, a 2 cm mucosal incision is made approximately 5 cm proximal to the submucosal tumor (SMT); B: A submucosal tunnel is created using endoscopic submucosal dissection; C: The submucosal dissection is continued until the SMT is visible by endoscopy; D: Dissection is performed along the margin of the SMT with an endoscopic knife; E: The dissected SMT is removed through the mucosal defect.

Figure 2 Laparoscopic endoscopic cooperative surgery. A: Three-fourths of the circumference is cut in the endoscopic side; B: Laparoscopic seromuscular dissection is performed along the submucosal dissection line; C: With the tumor and the non-resected portion are lifted, the defect is closed with laparoscopic linear staplers; D: The direction of stapling should be perpendicular to the longitudinal axis of the stomach.

Figure 3 Non-exposed endoscopic wall-inversion surgery. A: Laparoscopic seromuscular dissection is done after endoscopic submucosal injection. Then, laparoscopic seromuscular suture is performed around the dissected portion; B: Subsequently, the dissected portion is invaginated to the luminal side; C: The mucosal layer is cut with the endoscopic device.