Basic Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. Feb 15, 2023; 15(2): 303-317
Published online Feb 15, 2023. doi: 10.4251/wjgo.v15.i2.303
Increased CD4/CD8 Lymphocyte ratio predicts favourable neoadjuvant treatment response in gastric cancer: A prospective pilot study
Daniel Skubleny, Andrea Lin, Saurabh Garg, Ross McLean, Michael McCall, Sunita Ghosh, Jennifer L Spratlin, Daniel Schiller, Gina Rayat
Daniel Skubleny, Department of Surgery, University of Alberta, Edmonton T6G 2R3, AB, Canada
Andrea Lin, Saurabh Garg, Michael McCall, Daniel Schiller, Gina Rayat, Department of Surgery, University of Alberta, Edmonton T6G 2R3, Alberta, Canada
Ross McLean, Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton T6G 2R3, Alberta, Canada
Sunita Ghosh, Department of Oncology, University of Alberta, Edmonton T6G 2R3, Alberta, Canada
Jennifer L Spratlin, Department of Oncology, Cross Cancer Institute, University of Alberta, Edmonton T5G 1Z2, AB, Canada
Author contributions: Skubleny D, McCall M, Ghosh S, Spratlin JL, Schiller D and Rayat G designed and coordinated the study; Skubleny D, Lin A, Garg S, McLean R performed experiments, generated and analyzed data; McLean R evaluated biopsy pathology and presence of cancer; Skubleny D, Ghosh S, Schiller D and Rayat G interpreted the data; Skubleny D wrote the manuscript with editorial assistance from Ghosh S, Spratlin JL, Schiller D and Rayat G.
Institutional review board statement: All human clinical participants consented according to the approved ethics protocol granted by the Health Research Ethics Board of Alberta (Study ID: HREBA.CC-17-0228_REN5).
Informed consent statement: Informed consent according to an approved ethics protocol from the Health Research Ethics Board of Alberta (HREBA.CC-17-0228) was obtained for all patients.
Conflict-of-interest statement: All authors have no conflicts of interest to disclose.
Data sharing statement: Raw data and code are available from the corresponding author at skubleny@ualberta.ca.
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: Daniel Skubleny, MD, PhD, Doctor, Department of Surgery, University of Alberta, 116 St & 85 Ave, Edmonton T6G 2R3, AB, Canada. skubleny@ualberta.ca
Received: October 3, 2022
Peer-review started: October 3, 2022
First decision: October 24, 2022
Revised: November 25, 2022
Accepted: January 12, 2023
Article in press: January 12, 2023
Published online: February 15, 2023
Processing time: 134 Days and 1.1 Hours
Abstract
BACKGROUND

Despite optimal neoadjuvant chemotherapy only 40% of gastric cancer tumours achieve complete or partial treatment response. In the absence of treatment response, neoadjuvant chemotherapy in gastric cancer contributes to adverse events without additional survival benefit compared to adjuvant treatment or surgery alone. Additional strategies and methods are required to optimize the allocation of existing treatment regimens such as FLOT chemotherapy (5-Fluorouracil, Leucovorin, Oxaliplatin and Docetaxel). Predictive biomarkers detected using immunohistochemistry (IHC) methods may provide useful data regarding treatment response.

AIM

To investigate the utility of CD4, CD8, Galectin-3 and E-cadherin in predicting neoadjuvant FLOT chemotherapy tumour response in gastric adenocarcinoma.

METHODS

Forty-three adult patients with gastric adenocarcinoma, of which 18 underwent neoadjuvant chemotherapy, were included in a prospective clinical cohort. Endoscopic biopsies were obtained from gastric cancer and normal adjacent gastric mucosa. Differences in expression of Galectin-3, E-cadherin, CD4+ and CD8+ molecules between tumours with and without treatment response to neoadjuvant chemotherapy were assessed with IHC. Treatment response was graded by clinical pathologists using the Tumour Regression Score according to the College of American Pathologists criteria. Treatment response was defined as complete or near complete tumour response, whereas partial or poor/no response was defined as incomplete. Digital IHC images were annotated and quantitatively assessed using QuPath 0.3.1. Biomarker expression between responsive and incomplete response tumours was assessed using a two-sided Wilcoxon test. Biomarker expression was also compared between normal and cancer tissue and between 15 paired tumour samples before and after chemotherapy. We performed a preliminary multivariate analysis and power analysis to guide future study. Statistical analyses were completed using R 4.1.2.

RESULTS

The ratio between CD4+ and CD8+ lymphocytes was significantly greater in treatment responsive tumours (Wilcoxon, P = 0.03). In univariate models, CD4+/CD8+ ratio was the only biomarker that significantly predicted favourable treatment response (Accuracy 86%, P < 0.001). Using a glmnet multivariate model, high CD4+/CD8+ ratio and low Galectin-3 expression were the most influential variables in predicting a favourable treatment response. Analyses of paired samples found that FLOT chemotherapy also results in increased expression of CD4+ and CD8+ tumour infiltrating lymphocytes (Paired Wilcoxon, P = 0.002 and P = 0.008, respectively). Our power analysis suggests future study requires at least 35 patients in each treatment response group for CD8 and Galectin-3 molecules, whereas 80 patients in each treatment response group are required to assess CD4 and E-cadherin biomarkers.

CONCLUSION

We demonstrate that an elevated CD4+/CD8+ Ratio is a promising IHC-based biomarker to predict favourable treatment response to FLOT neoadjuvant chemotherapy in locally advanced gastric cancer.

Keywords: CD4; CD8; Galectin-3; Neoadjuvant chemotherapy; Treatment response; Gastric cancer

Core Tip: In the absence of treatment response, neoadjuvant chemotherapy for gastric cancer may contribute to adverse events without additional survival benefit compared to adjuvant treatment or surgery alone. Identifying patients that are likely to achieve favourable tumour response following neoadjuvant chemotherapy is of critical importance. In this pilot study, we investigate the utility of CD4, CD8, Galectin-3 and E-cadherin molecules in predicting which patients will benefit from neoadjuvant therapy using immunohistochemistry in pre-treatment biopsies. We demonstrate that an elevated ratio between CD4+ and CD8+ lymphocytes is a promising biomarker to predict treatment response to neoadjuvant chemotherapy in locally advanced gastric cancer.