Retrospective Study
Copyright ©The Author(s) 2022. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Jan 21, 2022; 10(3): 856-869
Published online Jan 21, 2022. doi: 10.12998/wjcc.v10.i3.856
Evaluating tumor-infiltrating lymphocytes in hepatocellular carcinoma using hematoxylin and eosin-stained tumor sections
Min Du, Yu-Meng Cai, Yu-Lei Yin, Li Xiao, Yuan Ji
Min Du, Yu-Lei Yin, Li Xiao, Department of Pathology, Huadong Hospital, Fudan University, Shanghai 200040, Shanghai Province, China
Yu-Meng Cai, Yuan Ji, Department of Pathology, Zhongshan Hospital, Fudan University, Shanghai 200032, Shanghai Province, China
Author contributions: Du M performed the research; Cai YM contributed to data collection and analysis; Yin YL and Xiao L helped in data analysis and modification of the manuscript; Yuan J contributed to the conception and design of the study; and all authors have read and approved the final manuscript.
Institutional review board statement: The study was approved by the Human Ethics Institutional Review Board of Huadong Hospital, Fudan University (approval number 2019K119).
Informed consent statement: Informed consent was waived by the Review Board because of the nature of retrospective study.
Conflict-of-interest statement: We have no financial relationships 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: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Yuan Ji, MD, Chief Doctor, Professor, Teacher, Department of Pathology, Zhongshan Hospital, Fudan University, No. 180 Fenglin Road, Xuhui Area, Shanghai 200032, Shanghai Province, China. ji.yuan@zs-hospital.sh.cn
Received: August 18, 2021
Peer-review started: August 18, 2021
First decision: September 29, 2021
Revised: October 13, 2021
Accepted: December 23, 2021
Article in press: December 23, 2021
Published online: January 21, 2022
Processing time: 150 Days and 4.6 Hours
Abstract
BACKGROUND

Tumor-infiltrating lymphocytes (TILs) constitute a prognostic factor in hepatocellular carcinoma (HCC). However, different methods of assessing TILs have various pre-analytical, analytical, and post-analytical challenges. The evaluation of TILs in hematoxylin and eosin (H&E)-stained tumor sections proposed by the International Immuno-Oncology Biomarker Working Group was demonstrated to be a reproducible, affordable and easily applied method in many tumors.

AIM

To evaluate the prognostic significance of TILs in H&E-stained slides of HCCs.

METHODS

This was a retrospective study performed in the hospital. HCC patients who underwent liver resection between 2015 and 2017 in Zhongshan Hospital were enrolled in this study. Patients who experienced recurrence or received therapy in addition to antiviral therapy before surgery at this time were excluded. A total of 204 patients were enrolled in the study. The ILs were counted manually in tumor sections stained with H&E under an optical microscope at 400 ×. The ILs were assessed separately in the center of the tumor (TILsCT), the invasive front (TILsIF), and peritumor (PILs) areas. Univariate and multivariate survival analyses were performed using a Cox regression model. P < 0.05 was considered statistically significant and all P-values were two-sided.

RESULTS

Among the 204 patients, univariate analysis indicated that macrovascular invasion (MaVI) (P = 0.001), microvascular invasion (MVI) (P = 0.012), multiple tumors (P = 0.008), large tumors (> 10 cm) (P = 0.001), absence of a tumor capsule (P = 0.026), macrotrabecular histological subtype (P = 0.001), low density of TILsCT (P = 0.039), TILsIF (P = 0.014), and PILs (P = 0.010) were predictors of progression-free survival (PFS). Cox multivariate analysis indicated that MaVI (P = 0.009), absence of a tumor capsule (P = 0.031), low-density of TILsIF (P = 0.047) and PILs (P = 0.0495) were independent predictors of PFS. A three-category analysis was carried out by combining TILsCT, TILsIF, and PILs, after which HCCs were classified into immunehigh [(TILsCT)high, (TILsIF)high, and PILshigh, 83 cases], immunemod (tumors other than immunehigh and immunelow subtypes, 94 cases), and immunelow [(TILsCT)low, (TILsIF)low, and PILslow, 27 cases)] subtypes. The immunehigh subtype had a lower rate of MVI (40.96%) than the immunemod (61.70%, P = 0.017) and immunelow (66.67%, P = 0.020) subtypes. The recurrence rates of the immunehigh, immunemod and immunelow subtypes were 10.8%, 25.5% and 33.3%, respectively.

CONCLUSION

HCC patients with high infiltrating lymphocytes tend to have a lower recurrence rate and less MVI. The evaluation of TILs in H&E-stained specimens could be a prognostic parameter for HCC.

Keywords: Lymphocytes; Tumor infiltration; Hepatocellular carcinoma; Hematoxylin and eosin-stained; Pathology

Core Tip: Successful use of immunotherapy in tumors starve for widely applicable, accessible and reliable immune-oncology biomarkers. Assessing tumor infiltrating lymphocytes (TILs) in hematoxylin and eosin (H&E)-stained tissues showed great clinical validity and utility in many solid tumors. However, barely any research on hepatocellular carcinoma (HCC) has been published. TILs evaluated in H&E-stained HCC tissues showed a great prognostic effect for recurrence in the present study and might be helpful to select patients with the highest likelihood of responding to immunotherapeutic agents. The method has low requirements in terms of technical and economic costs and can be easily applied in routine practice.