Endoscopic submucosal dissection for stomach neoplasms

Abstract

Recent advances in techniques of therapeutic endoscopy for stomach neoplasms are rapidly achieved. One of the major topics in this field is endoscopic submucosal dissection (ESD). ESD is a new endoscopic technique using cutting devices to remove the tumor by the following three steps: injecting fluid into the submucosa to elevate the tumor from the muscle layer, pre-cutting the surrounding mucosa of the tumor, and dissecting the connective tissue of the submucosa beneath the tumor. So the tumors are resectable in an en bloc fashion, regardless of the size, shape, coexisting ulcer, and location. Indication for ESD is strictly confined by two aspects: the possibility of nodal metastases and technical difficulty, which depends on the operators. Although long-term outcome data are still lacking, short-term outcomes of ESD are extremely favourable and laparotomy with gastrectomy is replaced with ESD in some parts of therapeutic strategy for early gastric cancer.

Figure 1

Devices for ESD. A: Needle knife (KD-1L-1, Olympus, Tokyo, Japan); B: IT (KD-610L, Olympus, Tokyo, Japan); C: Hook knife (KD-620LR, Olympus, Tokyo, Japan); D: Flex knife (KD-630L, Olympus, Tokyo, Japan); E: TT knife (KD-640L, Olympus, Tokyo, Japan); F: ST hood (DH-15GR, 15CR, Fujinon Toshiba ES Systems, Tokyo, Japan).

Figure 2

Endoscopic submucosal dissection (ESD). A: Ordinal endoscopy showing a whitish slight elevation with a blurred margin in the lesser curvature of the middle gastric body; B: Chromoendoscopy revealing margins of the lesion clearly; C: Marking dots on the circumference of the lesion; D: The incised mucosa around the marking dots of the distal margins; E: Before completion of circumferential mucosal incision, submucosal dissection from the distal edges; F: After mucosal incision with slight submucosal dissection circumferentially, submucosal dissection from the edge of the posterior wall to the anterior wall; G: Complete detachment of the lesion from the muscle layer and spraying sucralfate for confirmation of hemostasis; H: The resected specimen including the whole marking dots showing en bloc resection of the lesion.