Retrospective Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jan 7, 2018; 24(1): 87-95
Published online Jan 7, 2018. doi: 10.3748/wjg.v24.i1.87
Differential analysis of lymph node metastasis in histological mixed-type early gastric carcinoma in the mucosa and submucosa
Qian Zhong, Qi Sun, Gui-Fang Xu, Xiu-Qin Fan, Yuan-Yuan Xu, Fei Liu, Shi-Yi Song, Chun-Yan Peng, Lei Wang
Qian Zhong, Gui-Fang Xu, Xiu-Qin Fan, Yuan-Yuan Xu, Fei Liu, Shi-Yi Song, Chun-Yan Peng, Lei Wang, Department of Gastroenterology, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, Jiangsu Province, China
Qi Sun, Department of Pathology, the Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, Jiangsu Province, China
Author contributions: Zhong Q and Sun Q contributed equally to this work; Zhong Q and Wang L designed the research; Zhong Q and Sun Q contributed to the analysis and interpretation of the data; Xu GF, Fan XQ, Xu YY, Liu F, Song SY and Peng CY contributed to the acquisition of the data; Zhong Q, Wang L and Sun Q wrote the paper; all authors have read and approved the final version of the manuscript for publication.
Supported by Medical Science and Technology Development Foundation of Nanjing Department of Health, No. 201402032.
Institutional review board statement: The study was reviewed and approved by the Ethics Committee of The Affiliated Drum Tower Hospital of Nanjing University Medical School.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymized clinical data that were obtained after each patient agreed by written consent to undergo curative gastrectomy with lymph node dissection.
Conflict-of-interest statement: The authors have no conflicts of interest to disclose.
Data sharing statement: No additional data are available.
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: Lei Wang, MD, Department of Gastroenterology, the Affiliated Drum Tower Hospital of Nanjing University Medical School, No. 321, Zhongshan Road, Gulou District, Nanjing 210008, Jiangsu Province, China. 867152094@qq.com
Telephone: +86-25-83304616 Fax: +86-25-83304616
Received: October 5, 2017
Peer-review started: October 6, 2017
First decision: October 31, 2017
Revised: November 11, 2017
Accepted: November 27, 2017
Article in press: November 27, 2017
Published online: January 7, 2018
Abstract
AIM

To investigate the relationship between histological mixed-type of early gastric cancer (EGC) in the mucosa and submucosa and lymph node metastasis (LNM).

METHODS

This study included 298 patients who underwent gastrectomy for EGC between 2005 and 2012. Enrolled lesions were divided into groups of pure differentiated (pure D), pure undifferentiated (pure U), and mixed-type according to the proportion of the differentiated and undifferentiated components observed under a microscope. We reviewed the clinicopathological features, including age, sex, location, size, gross type, lymphovascular invasion, ulceration, and LNM, among the three groups. Furthermore, we evaluated the predictors of LNM in the mucosa-confined EGC.

RESULTS

Of the 298 patients, 165 (55.4%) had mucosa-confined EGC and 133 (44.6%) had submucosa-invasive EGC. Only 13 (7.9%) cases of mucosa-confined EGC and 30 (22.6%) cases of submucosa-invasive EGC were observed to have LNM. The submucosal invasion (OR = 4.58, 95%CI: 1.23-16.97, P = 0.023), pure U type (OR = 4.97, 95%CI: 1.21-20.39, P = 0.026), and mixed-type (OR = 5.84, 95%CI: 1.05-32.61, P = 0.044) were independent risk factors for LNM in EGC. The rate of LNM in mucosa-confined EGC was higher in the mixed-type group (P = 0.012) and pure U group (P = 0.010) than in the pure D group, but no significant difference was found between the mixed-type group and pure U group (P = 0.739). Similarly, the rate of LNM in the submucosa-invasive EGC was higher in the mixed-type (P = 0.012) and pure U group (P = 0.009) than in the pure D group but was not significantly different between the mixed-type and pure U group (P = 0.375). Multivariate logistic analysis showed that only female sex (OR = 5.83, 95%CI: 1.64-20.70, P = 0.028) and presence of lymphovascular invasion (OR = 13.18, 95%CI: 1.39-125.30, P = 0.020) were independent risk factors for LNM in mucosa-confined EGC, while histological type was not an independent risk factor for LNM in mucosa-confined EGC (P = 0.106).

CONCLUSION

For mucosal EGC, histological mixed-type is not an independent risk factor for LNM and could be managed in the same way as the undifferentiated type.

Keywords: Early gastric carcinoma, Mixed-type, Lymph node metastasis, Mucosa, Lymphovascular invasion

Core tip: This retrospective study investigated the relationship between the histological mixed-type of early gastric carcinoma (EGC) in the mucosa and submucosa and lymph node metastasis (LNM). We found that the rates of LNM in the histological mixed-type and the pure undifferentiated type were not significantly different in the mucosal or submucosal EGC. Furthermore, histological type was not an independent risk factor for LNM in mucosa-confined EGC. Hence, according to WHO classification, histological mixed-type and pure undifferentiated EGC could be managed in the same way, and curative endoscopic submucosal dissection is feasible for patients with histological mixed-type mucosa-confined EGC.