Yusuke Horiuchi1, Satoshi Ida2, Noriko Yamamoto3, Souya Nunobe2, Naoki Ishizuka4, Shoichi Yoshimizu5, Akiyoshi Ishiyama5, Toshiyuki Yoshio5, Toshiaki Hirasawa5, Tomohiro Tsuchida5, Koshi Kumagai2, Manabu Ohashi2, Takeshi Sano2, Junko Fujisaki5. 1. Department of Gastroenterology, Cancer Institute Hospital, 3-10-6 Ariake, Koto-ku, Tokyo, 135-8550, Japan. yusuke.horiuchi@jfcr.or.jp. 2. Department of Gastric Surgery, Cancer Institute Hospital, 3-10-6 Ariake, Koto-ku, Tokyo, 135-8550, Japan. 3. Department of Pathology, Cancer Institute Hospital, 3-10-6 Ariake, Koto-ku, Tokyo, 135-8550, Japan. 4. Department of Clinical Trial Planning and Management, Cancer Institute Hospital, 3-10-6 Ariake, Koto-ku, Tokyo, 135-8550, Japan. 5. Department of Gastroenterology, Cancer Institute Hospital, 3-10-6 Ariake, Koto-ku, Tokyo, 135-8550, Japan.
Abstract
BACKGROUND: Based on Japanese guidelines for endoscopic submucosal dissection (ESD) in undifferentiated-type early gastric cancer (UD-EGC), UD-predominant mixed-type (M-UD) EGC is considered high risk for lymph node metastasis (LNM). However, differences in LNM risk between pure UD (P-UD) and M-UD remain unclear. This study assessed risk factors for LNM considering differences between P-UD and M-UD and identified pathological features related to the lowest LNM risk. METHODS: This single-center, retrospective study included 1425 patients with UD-EGC treated with surgical resection between April 2005 and May 2017. We divided patients into those with and without LNM and compared background characteristics and post-operative pathological results between groups. Patients were further stratified based on depth, tumor diameter, ulcerative findings, lymphatic invasion, vascular invasion, and histological type to clarify post-operative pathological features associated with the lowest LNM risk. RESULTS: When comparing background characteristics and post-operative pathological results, multivariate analysis showed that, in patients with LNM, tumor diameters were significantly larger, and there were higher rates of submucosal invasion, lymphatic invasion, and M-UD histological type. In patients with absence of ulcerative findings, absence of lymphatic invasion, and absence of vascular invasion, no LNM occurred among those with intramucosal P-UD tumor diameters of 1-40 mm (1-20 mm: 95% confidence interval [CI], 0-5.5%; 21-40 mm: 95% CI, 0-6.1%). CONCLUSIONS: Intramucosal P-UD EGC patients with absence of ulcerative findings, absence of lymphatic invasion, absence of vascular invasion, and tumor diameters of ≤ 40 mm did not show LNM. We suggest expanding indications for ESD to include these patients.
BACKGROUND: Based on Japanese guidelines for endoscopic submucosal dissection (ESD) in undifferentiated-type early gastric cancer (UD-EGC), UD-predominant mixed-type (M-UD) EGC is considered high risk for lymph node metastasis (LNM). However, differences in LNM risk between pure UD (P-UD) and M-UD remain unclear. This study assessed risk factors for LNM considering differences between P-UD and M-UD and identified pathological features related to the lowest LNM risk. METHODS: This single-center, retrospective study included 1425 patients with UD-EGC treated with surgical resection between April 2005 and May 2017. We divided patients into those with and without LNM and compared background characteristics and post-operative pathological results between groups. Patients were further stratified based on depth, tumor diameter, ulcerative findings, lymphatic invasion, vascular invasion, and histological type to clarify post-operative pathological features associated with the lowest LNM risk. RESULTS: When comparing background characteristics and post-operative pathological results, multivariate analysis showed that, in patients with LNM, tumor diameters were significantly larger, and there were higher rates of submucosal invasion, lymphatic invasion, and M-UD histological type. In patients with absence of ulcerative findings, absence of lymphatic invasion, and absence of vascular invasion, no LNM occurred among those with intramucosal P-UD tumor diameters of 1-40 mm (1-20 mm: 95% confidence interval [CI], 0-5.5%; 21-40 mm: 95% CI, 0-6.1%). CONCLUSIONS: Intramucosal P-UD EGCpatients with absence of ulcerative findings, absence of lymphatic invasion, absence of vascular invasion, and tumor diameters of ≤ 40 mm did not show LNM. We suggest expanding indications for ESD to include these patients.
Authors: K Okada; J Fujisaki; T Yoshida; H Ishikawa; T Suganuma; A Kasuga; M Omae; M Kubota; A Ishiyama; T Hirasawa; A Chino; M Inamori; Y Yamamoto; N Yamamoto; T Tsuchida; Y Tamegai; A Nakajima; E Hoshino; M Igarashi Journal: Endoscopy Date: 2012-01-23 Impact factor: 10.093