Usefulness of Endoscopic Submucosal Dissection (esd) Versus Conventional EMR for Superficial Gastric Lesions

Abstract

Usefulness of Endoscopic Submucosal Dissection (esd) Versus Conventional EMR for Superficial Gastric Lesions Manabu Nakagawa, Souichi Nakagawa, Yuichi Shimizu, Mototsugu Kato, Yuji Ono, Takehiko Katsurada, Shoko Ono, Yosuke Miura, Yasuaki Mori, Jyunji Yamamoto, Toshifumi Hayakawa, Yoshito Komatsu, Hiroshi Takeda, Masahiro Asaka Background and Aim: En-bloc resection is desirable for accurate pathological assessment of tissue specimens obtained by endoscopic mucosal resection (EMR). Using a new EMR method, endoscopic submucosal dissection (ESD) method, enbloc resections can be successfully carried out on large superficial gastric lesions greater than 20 mm in diameter. However the rate of complications in patients undergoing ESD is high, and a safe ESD method is therefore needed. To prevent complications, we performed ESD using an injection of sodium hyarulonate with a small-caliber-tip transparent hood (ST hood) attached to the end of the endoscope. This method enables easier submucosal incision. The aim of this study was to evaluate the therapeutic quality of ESD by comparison with the conventional EMR method. Patients and Methods: ESD was performed as follows: 1) placement of markings for the incision line, 2) submucosal injections of sodium hyaluronate under and around the lesion, 3) circumferential mucosal incision around the tumor with an insulated-tip knife (IT knife), and 4) submucosal incision with the needleknife (flat type) through the ST hood. A total of 140 patients with early gastric carcinoma or gastric adenoma were enrolled in this study during the period from 2002 to 2004. They were divided into two groups: a conventional EMR (doublechannel method and endoscopic aspiration mucosectomy) group and an ESD group. Rates of en-bloc resection, curative resection, and complications in the two groups were compared. Results: Seventy-eight cases in the conventional EMR group and 58 cases in the ESD group were finally investigated. There was no significant difference between the two groups in age or sex, but significant differences were found in mean size of the tumor (12.4 G 6.9 cm vs. 26.3 G 13.4 cm; p ! 0.01) and pathological findings (adenoma/carcinoma: 27/51 vs. 6/52; p ! 0.01). The rates of en-bloc resection, curative resection and complications were 52.6% (41/78), 51.3% (40/78) and 9.0% (7/78; bleeding, 5; perforation, 2) in the conventional EMR group and 94.8% (55/58), 93.1% (54/58) and 1.7% (1/58; bleeding, 1) in the ESD group, respectively. The rates of en-bloc resection and curative resection were significantly higher in the ESD group (p ! 0.01), but there was no significant difference between the rates of complications (p Z 0.07) in the two groups. Conclusion: The ESD method for superficial gastric tumors is safe and enables high-quality resection.