Meta-Analysis
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Feb 28, 2021; 27(8): 737-750
Published online Feb 28, 2021. doi: 10.3748/wjg.v27.i8.737
Risk factors for lymph node metastasis in T1 esophageal squamous cell carcinoma: A systematic review and meta-analysis
Kai-Yuan Jiang, Heng Huang, Wei-Yang Chen, Hao-Ji Yan, Zhen-Ting Wei, Xiao-Wen Wang, Hao-Xuan Li, Xiang-Yun Zheng, Dong Tian
Kai-Yuan Jiang, Heng Huang, Wei-Yang Chen, Hao-Ji Yan, Zhen-Ting Wei, Xiao-Wen Wang, Hao-Xuan Li, Xiang-Yun Zheng, College of Clinical Medicine, North Sichuan Medical College, Nanchong 637000, Sichuan Province, China
Kai-Yuan Jiang, Dong Tian, Department of Thoracic Surgery, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, Sichuan Province, China
Author contributions: Jiang KY, Huang H and Tian D designed the research; Jiang KY and Huang H performed the research and drafted the article; Chen WY, Yan HJ and Wei ZT screened the literature and collected the data; Wang XW, Li HX and Zheng XY analyzed the data and interpreted the data; Tian D revised the article; All authors have read and approved the final manuscript; Jiang KY and Huang H contributed equally to this work.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
PRISMA 2009 Checklist statement: The authors have read the PRISMA 2009 Checklist, and the manuscript was prepared and revised according to the PRISMA 2009 Checklist.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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/
Corresponding author: Dong Tian, MD, PhD, Doctor, Department of Thoracic Surgery, Affiliated Hospital of North Sichuan Medical College, No. 63 Wenhua Road, Shunqing District, Nanchong 637000, Sichuan Province, China. 22tiandong@163.com
Received: November 28, 2020
Peer-review started: November 28, 2020
First decision: January 17, 2021
Revised: January 20, 2021
Accepted: February 1, 2021
Article in press: February 1, 2021
Published online: February 28, 2021
Abstract
BACKGROUND

Lymph node metastasis (LNM) affects the application and outcomes of endoscopic resection in T1 esophageal squamous cell carcinoma (ESCC). However, reports of the risk factors for LNM have been controversial.

AIM

To evaluate risk factors for LNM in T1 ESCC.

METHODS

We searched Embase, PubMed and Cochrane Library to select studies related to LNM in patients with T1 ESCC. Included studies were divided into LNM and non-LNM groups. We performed a meta-analysis to examine the relationship between LNM and clinicopathologic features. Odds ratio (OR), mean differences and 95% confidence interval (CI) were assessed using a fixed-effects or random-effects model.

RESULTS

Seventeen studies involving a total of 3775 patients with T1 ESCC met the inclusion criteria. After excluding studies with heterogeneity based on influence analysis, tumor size (OR = 1.93, 95%CI = 1.49-2.50, P < 0.001), tumor location (OR = 1.46, 95%CI = 1.17-1.82, P < 0.001), macroscopic type (OR = 3.17, 95%CI = 2.33-4.31, P < 0.001), T1 substage (OR = 6.28, 95%CI = 4.93-8.00, P < 0.001), differentiation (OR = 2.11, 95%CI = 1.64-2.72, P < 0.001) and lymphovascular invasion (OR = 5.86, 95%CI = 4.60-7.48, P < 0.001) were found to be significantly associated with LNM. Conversely, sex, age and infiltrative growth pattern were not identified as risk factors for LNM.

CONCLUSION

A tumor size > 2 cm, lower location, nonflat macroscopic type, T1b stage, poor differentiation and lymphovascular invasion were associated with LNM in patients with T1 ESCC.

Keywords: Risk factors, Lymph node metastasis, T1, Esophageal squamous cell carcinoma, Meta-analysis, Review

Core Tip: No consensus is available in the literature about risk factors for lymph node metastasis (LNM) in T1 esophageal squamous cell carcinoma. This meta-analysis is the first to comprehensively evaluate LNM only in esophageal squamous cell carcinoma patients with T1 stage. We investigated the relationship between LNM and the factors of demographic and clinicopathological characteristics. The results showed that risk factors associated with LNM were tumor size, tumor location, T1 substage, tumor differentiation, lymphovascular invasion and macroscopic type.