Reevaluation of the expanded indications in undifferentiated early gastric cancer for endoscopic submucosal dissection

Figure 1 Flow chart of study patients. EGC: Early gastric cancer; SM: Submucosa; LVI: Lymphovascular invasion.

Figure 2 Blurring of muscularis mucosa underneath the tumorous epithelium. Representative images of tumors with diffuse, focal, and no blurring of muscularis mucosa. A: Diffuse blurring of muscularis mucosa (MM) was prominent enough to localize the tumor at scanning magnification (arrowhead); B: At higher magnification (40´), the thickness of MM appeared irregular due to collagen fibers disrupting the muscle fibers of MM; C: The majority of MM underneath the tumorous epithelium (both ends are marked by arrows) was undisrupted compared with adjacent MM underneath the non-tumorous epithelium, making the foci of MM blurring focal (arrowhead); D: With no blurring of MM, it was difficult to localize the tumor (both ends are marked by arrows) at scanning magnification based on the status of MM.

Figure 3 Endoscopic images of the cases with lymph node metastasis without exudate, mucosal break, converging fold, and tumor island. A: Case 1, B: Case 3, C: Case 5, D: Case 9.