Observational Study
Copyright ©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Oncol. May 15, 2024; 16(5): 1878-1889
Published online May 15, 2024. doi: 10.4251/wjgo.v16.i5.1878
Correlation of tumor-associated macrophage density and proportion of M2 subtypes with the pathological stage of colorectal cancer
Fouzia Fazal, Muhammad Arsalan Khan, Sumayya Shawana, Rahma Rashid, Muhammed Mubarak
Fouzia Fazal, Department of Pathology, Jinnah Medical and Dental College, Karachi 74800, Sindh, Pakistan
Muhammad Arsalan Khan, Department of General Surgery, Sindh Institute of Urology & Transplantation (SIUT), Karachi 74200, Sindh, Pakistan
Sumayya Shawana, Department of Pathology, Bahria University of Health Sciences, Karachi 74400, Sindh, Pakistan
Rahma Rashid, Muhammed Mubarak, Department of Pathology, SIUT, Karachi 74200, Sindh, Pakistan
Author contributions: Fazal F, Khan MA, Shawana S, Rashid R, and Mubarak M contributed significantly and equally to the preparation of the manuscript; Fazal F and Shawana S conceived and designed the study; Fazal F, Khan MA, Shawana S, Rashid R, and Mubarak M performed the research; All five authors participated in primary and final drafting, and all read and approved the final manuscript.
Institutional review board statement: The study was reviewed and approved by the Bahria University Medical and Dental College Institutional Review Board (Approval No. FRC-BUMDC-13/2020-Path-115).
Informed consent statement: All study participants provided informed written consent prior to study enrollment.
Conflict-of-interest statement: None of the authors has any conflict of interest to disclose.
Data sharing statement: The data will be available with the primary author of the manuscript and can be furnished on reasonable request.
STROBE statement: The authors have read the STROBE Statement—checklist of items, and the manuscript was prepared and revised according to the STROBE Statement—checklist of items.
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: Muhammed Mubarak, MD, Professor, Department of Pathology, SIUT, Chand Bibi Road, DFMC, Karachi 74200, Sindh, Pakistan. drmubaraksiut@yahoo.com
Received: November 17, 2023
Peer-review started: November 17, 2023
First decision: December 12, 2023
Revised: December 14, 2023
Accepted: March 26, 2024
Article in press: March 26, 2024
Published online: May 15, 2024
Processing time: 174 Days and 1 Hours
Abstract
BACKGROUND

Colorectal cancer (CRC) is a prevalent global malignancy with complex prognostic factors. Tumor-associated macrophages (TAMs) have shown paradoxical associations with CRC survival, particularly concerning the M2 subset.

AIM

We aimed to establish a simplified protocol for quantifying M2-like TAMs and explore their correlation with clinicopathological factors.

METHODS

A cross-sectional study included histopathological assessment of paraffin-embedded tissue blocks obtained from 43 CRC patients. Using CD68 and CD163 immunohistochemistry, we quantified TAMs in tumor stroma and front, focusing on M2 proportion. Demographic, histopathological, and clinical parameters were collected.

RESULTS

TAM density was significantly higher at the tumor front, with the M2 proportion three times greater in both zones. The tumor front had a higher M2 proportion, which correlated significantly with advanced tumor stage (P = 0.04), pathological nodal involvement (P = 0.04), and lymphovascular invasion (LVI, P = 0.01). However, no significant association was found between the M2 proportion in the tumor stroma and clinicopathological factors.

CONCLUSION

Our study introduces a simplified protocol for quantifying M2-like TAMs in CRC tissue samples. We demonstrated a significant correlation between an increased M2 proportion at the tumor front and advanced tumor stage, nodal involvement, and LVI. This suggests that M2-like TAMs might serve as potential indicators of disease progression in CRC, warranting further investigation and potential clinical application.

Keywords: Colorectal cancer; Macrophages; Tumor stroma; M2 subset; Tumor front; Tumor stage; Lymphovascular invasion; Prognosis; Tumor-associated macrophages; Immunohistochemistry

Core Tip: Colorectal cancer is a highly prevalent type of cancer worldwide. Its prognosis depends on several factors including pathological features. Novel prognostic factors with improved predictive and prognostic potential are being sought. Tumor-associated macrophages have been investigated as a novel biomarker for improved prognosis and theragnosis.