Review
Copyright ©The Author(s) 2020. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Apr 26, 2020; 8(8): 1350-1360
Published online Apr 26, 2020. doi: 10.12998/wjcc.v8.i8.1350
Predictive factors for central lymph node metastases in papillary thyroid microcarcinoma
Xin Wu, Bing-Lu Li, Chao-Ji Zheng, Xiao-Dong He
Xin Wu, Bing-Lu Li, Chao-Ji Zheng, Xiao-Dong He, Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
Author contributions: All authors helped to write the paper; Wu X wrote the manuscript and analyzed the data; Li BL contributed to the conception and design of the paper and analyzed the data; Zheng CJ and He XD contributed to the writing of the manuscript and the conception and design of the paper.
Supported by Fundamental Research Funds for the Central Universities of China, No. 3332019022.
Conflict-of-interest statement: The authors declare no conflict of interests for this article.
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: Bing-Lu Li, MD, Professor, Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No. 1, Shuaifuyuan, Dongcheng District, Beijing 100730, China. pumchlibinglu@163.com
Received: January 11, 2020
Peer-review started: January 11, 2020
First decision: February 26, 2020
Revised: March 4, 2020
Accepted: April 4, 2020
Article in press: April 4, 2020
Published online: April 26, 2020
Processing time: 104 Days and 1.4 Hours
Abstract

Papillary thyroid microcarcinoma (PTMC) measures 1 cm or less in its longest dimension. The incidence of PTMC is increasing worldwide. Surgery is the primary treatment; however, prophylactic central lymph node dissection is controversial, and discrepancies between different guidelines have been noted. Routine prophylactic central lymph node dissection may result in hypoparathyroidism and recurrent laryngeal nerve injury in some patients without lymph node metastasis, while simple thyroidectomy may leave metastatic lymph nodes in high-risk patients. To selectively perform prophylactic lymph node dissections in high-risk patients, it is important to identify predictive factors for lymph node metastases in patients with PTMC. Several studies have reported on this, but their conclusions are not entirely consistent. Several clinicopathologic characteristics have been identified as risk factors for central lymph node metastases, and the most commonly reported factors include age, gender, tumor size and location, multifocality, bilaterality, extrathyroidal extension, and abnormal lymph node found using ultrasound. Here, we provide an overview of previous studies along with a favorable opinion on or against these factors, with the aim of increasing the understanding of this topic among the medical community. In addition, current opinions about prophylactic central lymph node dissection are reviewed and discussed.

Keywords: Papillary thyroid carcinoma; Papillary thyroid microcarcinoma; Central lymph node dissection; Prophylactic; Risk factor; Prognosis

Core tip: Surgery is the primary treatment for papillary thyroid microcarcinoma. Prophylactic central lymph node dissection is controversial due to its potential oncologic benefit and side effects. This review provides an overview of previous studies on the predictive factors for lymph node metastases in patients with papillary thyroid microcarcinoma. The most commonly reported factors include age, gender, tumor size and location, multifocality, bilaterality, extrathyroidal extension, and abnormal lymph node found using ultrasound. Prophylactic central neck dissection should be selectively performed only in high-risk patients.