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Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Aug 15, 2022; 14(8): 1429-1445
Published online Aug 15, 2022. doi: 10.4251/wjgo.v14.i8.1429
Lymph node regression grading of locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy
Lei He, Juan Xiao, Ping Zheng, Lei Zhong, Qian Peng
Lei He, Juan Xiao, School of Medicine, University of Electronic Science and Technology of China, Chengdu 611731, Sichuan Province, China
Ping Zheng, Department of Pathology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, Sichuan Province, China
Lei Zhong, Personalized Drug Therapy Key Laboratory of Sichuan Province, Sichuan Academy of Medical Sciences and Sichuan Provincial People’s Hospital, Chengdu 610072, Sichuan Province, China
Qian Peng, Radiation Therapy Center, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, Chengdu 610041, Sichuan Province, China
Author contributions: He L performed the literature review and wrote the paper; He L, Xiao J, Zhong L, and Zheng P collected the pathology data; all authors have read and approved the final manuscript.
Supported by Chengdu Science and Technology Project, No. 2021-YF05-01484-SN; Excellent Youth Foundation Project of Sichuan Cancer Hospital, No. YB2021037; and Foundation Project of Health Commission of Sichuan Province, No. 20PJ112.
Conflict-of-interest statement: The authors declare no conflicts of interest 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: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Qian Peng, MD, PhD, Associate Chief Physician, Doctor, Radiation Therapy Center, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, School of Medicine, University of Electronic Science and Technology of China, No. 55 Section 4, Renmin South Road, Chengdu 610041, Sichuan Province, China. pengqian0522@163.com
Received: March 8, 2022
Peer-review started: March 8, 2022
First decision: April 17, 2022
Revised: April 30, 2022
Accepted: July 6, 2022
Article in press: July 6, 2022
Published online: August 15, 2022
Processing time: 155 Days and 4 Hours
Abstract

Neoadjuvant chemoradiotherapy (nCRT) and total rectal mesenteric excision are the main standards of treatment for locally advanced rectal cancer (LARC). Lymph node regression grade (LRG) is an indicator of prognosis and response to preoperative nCRT based on postsurgical metastatic lymph node pathology. Common histopathological findings in metastatic lymph nodes after nCRT include necrosis, hemorrhage, nodular fibrosis, foamy histiocytes, cystic cell reactions, areas of hyalinosis, residual cancer cells, and pools of mucin. A number of LRG systems designed to classify the amount of lymph node regression after nCRT is mainly concerned with the relationship between residual cancer cells and regressive fibrosis and with estimating the number of lymph nodes existing with residual cancer cells. LRG offers significant prognostic information, and in most cases, LRG after nCRT correlates with patient outcomes. In this review, we describe the systematic classification of LRG after nCRT, patient prognosis, the correlation with tumor regression grade, and the typical histopathological findings of lymph nodes. This work may serve as a reference to help predict the clinical complete response and determine lymph node regression in patients based on preservation strategies, allowing for the formulation of more accurate treatment strategies for LARC patients, which has important clinical significance and scientific value.

Keywords: Lymph node regression grade; Histopathological; Rectal cancer; Chemoradiotherapy; Treatment response; Neoadjuvant therapy

Core Tip: Studies on lymph node regression grading after neoadjuvant chemoradiotherapy (nCRT) for rectal cancer are limited but serve clinicians for assessing the lymph node response to treatment based on the efficacy of the primary tumor after preoperative nCRT, providing guidance in formulating more accurate surgical or therapeutic strategies for the next stage of patient management and in determining patient prognosis. We discuss its histopathology, prognosis, correlation with tumor regression grading, and clinical applications and prospects.