Figure 1.

Technical detail of non-exposed endoscopic wall-inversion surgery for gastric gastrointestinal stromal tumor. (A) Identification of the tumor location; (B) markings on the mucosa around the lesion; (C) markings on the serosa; (D) injection into the submucosal layer; (E,F) circumferential seromuscular layer cutting; (G-I) seromuscular suturing with inversion of the lesion with a gauze spacer; (J) extensive protrusion of the gastric mucosa due to the inverted tissue; (K-M) incision of the muco-submucosal layer; (N) endoscopic clips placement to close an artificial linear ulcer; (O) oral extraction using an endoscopic retrieval device.