Retrospective Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Mar 7, 2015; 21(9): 2683-2692
Published online Mar 7, 2015. doi: 10.3748/wjg.v21.i9.2683
Stratifying the risk of lymph node metastasis in undifferentiated-type early gastric cancer
Yukiko Asakawa, Masahiko Ohtaka, Shinya Maekawa, Mitsuharu Fukasawa, Yasuhiro Nakayama, Tatsuya Yamaguchi, Taisuke Inoue, Tomoyoshi Uetake, Minoru Sakamoto, Tadashi Sato, Yoshihiko Kawaguchi, Hideki Fujii, Kunio Mochizuki, Masao Hada, Toshio Oyama, Tomotaka Yasumura, Kosaku Omata, Atsushi Nishiyama, Keiichi Naito, Hideo Hata, Yoshiaki Haba, Kazuyuki Miyata, Haruhisa Saitoh, Yoichi Yamadera, Kazuo Miura, Akira Kawaoi, Tohru Abe, Hajime Tsunoda, Yuji Honda, Masayuki Kurosaki, Nobuyuki Enomoto
Yukiko Asakawa, Masahiko Ohtaka, Shinya Maekawa, Mitsuharu Fukasawa, Yasuhiro Nakayama, Tatsuya Yamaguchi, Taisuke Inoue, Tomoyoshi Uetake, Minoru Sakamoto, Tadashi Sato, Nobuyuki Enomoto, First Department of Internal Medicine, Faculty of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
Yoshihiko Kawaguchi, Hideki Fujii, First Department of Surgery, Faculty of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
Kunio Mochizuki, Department of Pathology, Faculty of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
Masao Hada, Department of Surgery, Yamanashi Prefectural Central Hospital, Yamanashi 400-8506, Japan
Toshio Oyama, Department of Pathology, Yamanashi Prefectural Central Hospital, Yamanashi 400-8506, Japan
Tomotaka Yasumura, Department of Surgery, Social Insurance Yamanashi Hospital, Yamanashi 400-0025, Japan
Kosaku Omata, Department of Pathology, Social Insurance Yamanashi Hospital, Yamanashi 400-0025, Japan
Atsushi Nishiyama, Keiichi Naito, Department of General Surgery, Kofu Kyoritsu Hospital, Yamanashi 400-0034, Japan
Hideo Hata, Department of Pathology, Kofu Kyoritsu Hospital, Yamanashi 400-0034, Japan
Yoshiaki Haba, Department of Surgery, Kofu Municipal Hospital, Yamanashi 400-0832, Japan
Kazuyuki Miyata, Department of Pathology, Kofu Municipal Hospital, Yamanashi 400-0832, Japan
Haruhisa Saitoh, Yoichi Yamadera, Department of Surgery, Yamanashi Kosei Hospital, Yamanashi 405-0033, Japan
Kazuo Miura, Department of Surgery, Kanoiwa General Hospital, Yamanashi 405-0018, Japan
Akira Kawaoi, Department of Pathology, Kanoiwa General Hospital, Yamanashi 405-0018, Japan
Tohru Abe, Department of Surgery, Social Insurance Kajikazawa Hospital, Yamanashi 400-0601, Japan
Hajime Tsunoda, Department of Surgery, Kofu National Hospital, Yamanashi 400-0006, Japan
Yuji Honda, Department of Surgery, Fujiyoshida Municipal Medical Center, Yamanashi 403-0005, Japan
Masayuki Kurosaki, Division of Gastroenterology and Hepatology, Musashino Red Cross Hospital, Tokyo 180-0023, Japan
Author contributions: Asakawa Y and Ohtaka M contributed to the conception and design; Asakawa Y, Ohtaka M, Kawaguchi Y, Fujii H, Mochizuki K, Hada M, Oyama T, Yasumura T, Omata K, Nishiyama A, Naito K, Hata H, Haba Y, Miyata K, Saitoh H, Yamadera Y, Miura K, Kawaoi A, Abe T, Tsunoda H, Honda Y and Kurosaki M contributed to the acquisition of data; Asakawa Y, Ohtaka M, Maekawa S, Fukasawa M, Nakayama Y, Yamaguchi T, Inoue T, Uetake T, Sakamoto M, Sato T and Enomoto N contributed to the analysis and interpretation of data; Asakawa Y, Ohtaka M, Maekawa S and Enomoto N contributed to the drafting or revising.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Masahiko Ohtaka, MD, PhD, First Department of Internal Medicine, Faculty of Medicine, University of Yamanashi, 1110, Shimokato, Chuo, Yamanashi 409-3898, Japan. motaka@yamanashi.ac.jp
Telephone: +81-55-2739584 Fax: +81-55-2736748
Received: June 30, 2014
Peer-review started: July 1, 2014
First decision: August 6, 2014
Revised: August 25, 2014
Accepted: October 15, 2014
Article in press: October 15, 2014
Published online: March 7, 2015
Abstract

AIM: To study how lymph node metastasis (LNM) risk is stratified in undifferentiated-type early gastric cancer (undiff-EGC) dependent on combinations of risk factors.

METHODS: Five hundred and sixty-seven cases with undiff-EGC undergoing gastrectomy with lymphadenectomy were examined retrospectively. Using clinicopathological factors of patient age, location, size, an endoscopic macroscopic tumor form, ulceration, depth, histology, lymphatic involvement (LI) and venous involvement (VI), LNM risk was examined and stratified by conventional statistical analysis and data-mining analysis.

RESULTS: LNM was positive in 44 of 567 cases (7.8%). Univariate analysis revealed > 2 cm, protrusion, submucosal (sm), mixed type, LI and VI as significant prognostic factors and > 2 cm and LI-positive were independent factors by multivariate analysis. In preoperatively evaluable factors excluding LVI, sm and > 2 cm were independent factors. According to the depth and size, cases were categorized into the low-risk group [m and ≤ 2 cm, 0% (LNM incidence)], the moderate-risk group (m and > 2 cm, 5.6%; and sm and ≤ 2 cm, 6.0%), and the high-risk group (sm and > 2 cm, 19.3%). On the other hand, LNM occurred in 1.4% in all LI-negative cases, greatly lower than 28.2% in all LI-positive cases, and LNM incidence was low in LI-negative cases even in the moderate- and high-risk groups.

CONCLUSION: LNM-related factors in undiff-EGC were depth and size preoperatively while those were LI and size postoperatively. Among these factors, LI was the most significantly correlated factor.

Keywords: Undifferentiated-type early gastric cancer, Lymph node metastasis, Lymphatic involvement, Data-mining analysis, Stratification

Core tip: The lymph node metastasis (LNM) risk in cases with undifferentiated-type early gastric cancer was evaluated and stratified using preoperatively as well as postoperatively evaluable factors. In preoperatively evaluable factors, the risk of LNM was predicted based on the size and depth and categorized into the low-risk group: mucosal cancer (m) and ≤ 2 cm, 0% (LNM incidence) (95%CI: 0-2.3), the moderate-risk group: m and > 2 cm, 5.6% (95%CI: 2.6-11.7); submucosal invasion (sm) and ≤ 2 cm, 6.0% (95%CI: 3.2-11.1), and the high-risk group: sm and > 2 cm, 19.3% (95%CI: 13.8-26.4). However, when the postoperatively evaluable factor of LI was included, cases with further lower or higher risk could be stratified even in the moderate- and high-risk groups. Some high-risk cases for surgery due to old age and concurrent disease could be reasonably followed-up after resection of the gastric lesion by endoscopic submucosal dissection.