Figure 1.

Procedure of endoscopic submucosal dissection: A male patient aged 56 years. A: Gastroscopy showed a type 0-IIa (2.5 cm × 1.8 cm) lesion in the greater curvature of the stomach and pathology revealed differentiated adenocarcinoma; B: Magnification was performed using narrow band imaging to determine the borderline; C: Point-like electric coagulation was done at 0.5 cm away from the borderline of lesion for marking; D: Following submucosal injection, a circumferential incision was made in the mucosa and submucosa at 0.5 cm away from the marks; E: The mucosas were dissected from submucosa using an insulation tipped-2 knife; F: Artificial ulcer following resection; G: The sample (4 cm × 3 cm) was unfolded and the marks were found in the sample; H: Pathological type was high-grade intraepithelial neoplasia (× 40).