Retrospective Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Apr 26, 2022; 10(12): 3709-3719
Published online Apr 26, 2022. doi: 10.12998/wjcc.v10.i12.3709
Relationship between subgroups of central and lateral lymph node metastasis in clinically node-negative papillary thyroid carcinoma
Jing Zhou, Da-Xue Li, Han Gao, Xin-Liang Su
Jing Zhou, Da-Xue Li, Han Gao, Department of Thyroid and Breast Surgery, Chongqing Health Center for Women and Children, Chongqing 401120, China
Xin-Liang Su, Department of Thyroid and Breast Surgery, First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, China
Author contributions: Zhou J and Li DX contributed equally to this work; Zhou J, Su XL and Gao H designed the research study; Zhou J, Li DX and Gao H performed the research; Su XL and Gao H contributed new analytic tools; Zhou J and Li DX analyzed the data and wrote the manuscript; all authors have read and approve the final manuscript.
Institutional review board statement: This study was reviewed and approved by the Ethics Committee of the First Affiliated Hospital of Chongqing Medical University. The research content and process of the project followed the international and national ethical requirements for biomedical research.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: All authors have no potential conflicts of interest to disclose.
Data sharing statement: No additional data are available.
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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Xin-Liang Su, MD, PhD, Professor, Surgical Oncologist, Department of Thyroid and Breast Surgery, First Affiliated Hospital of Chongqing Medical University, No. 1 Youyi Road, Yuzhong District, Chongqing 400016, China. suxinliang@21cn.com
Received: September 1, 2021
Peer-review started: September 1, 2021
First decision: October 25, 2021
Revised: November 8, 2021
Accepted: March 6, 2022
Article in press: March 6, 2022
Published online: April 26, 2022
ARTICLE HIGHLIGHTS
Research background

Prophylactic lateral lymph node dissection (LLND) is controversial for clinically node-negative papillary thyroid carcinoma (cN0-PTC), mainly due to the low accuracy of the preoperative diagnosis of cN0. CN0 is not equal to pathological node negative, and many researchers are working to identify risk factors for lateral lymph node metastasis (LNM) to realize selective prophylactic LLND.

Research motivation

The relationship between the central LNM and lateral LNM subgroups demonstrates a regularity in LNM in PTC. It is the basis of accurate surgical decisions by clinical surgeons.

Research objectives

To investigate the relationship between subgroups of central LNM and lateral LNM of unilateral cN0-PTC.

Research methods

The clinical and pathological data of 388 patients with unilateral cN0-PTC from the Endocrine Mammary Surgery Department of the First Affiliated Hospital of Chongqing Medical University from January 2016 to December 2017 were retrospectively analyzed. Optimal scaling regression analysis explained the relationship between subgroups of central LNM and lateral LNM of unilateral cN0-PTC.

Research results

The coincidence rate of cN0 was only 30.0%, and sex (57.1% vs 42.9%, P = 0.026), primary tumor size (68.8% vs 31.2%, P = 0.008), tumor location (59.7% vs 40.3%, P = 0.007), extrathyroid extension (ETE) (50.6% vs 49.9%, P =0.046), and prelaryngeal LNM (57.1% vs 42.9%, P = 0.004) were independent risk factors for ipsilateral level-II LNM. Primary tumor size (74.6% vs 30.2%, P = 0.016), pretracheal LNM (67.5% vs 32.5%, P < 0.001), and paratracheal LNM (71.4% vs 28.6%, P < 0.001) were independent risk factors for ipsilateral level-III LNM. Primary tumor size (72.1% vs 27.9%, P = 0.003), ETE (70.4% vs 29.6%, P = 0.016), pretracheal LNM (68.3% vs 31.7%, P = 0.001), and paratracheal LNM (80.8% vs 19.2%, P < 0.001) were independent risk factors for ipsilateral level-IV LNM.

Research conclusions

For unilateral cN0-PTC patients, different central LNM subgroups predicted different subgroups of lateral LNM, which is helpful for determining the extent of prophylactic lateral LND.

Research perspectives

For unilateral cN0-PTC patients with prelaryngeal LNM, LNM may occur at ipsilateral level-II, and prophylactic level-II LND can be considered. When pretracheal or ipsilateral paratracheal LNM occurs, LNM may occur at ipsilateral level III and level IV, and prophylactic level-III and level-IV LND can be considered.