Tumor-Associated Macrophage Infiltration and PD-L1 Expression in Gastric Cancer According to a Modified TCGA-Based Classification
- Author:
Boram SONG
1
;
Dong-Hoe KOO
;
Eo Jin KIM
;
In-Gu DO
;
Jinah CHU
;
Kyungeun KIM
;
Hyebin LEE
;
Min-Jung KWON
;
Jung Ho PARK
;
Byung Ho SON
;
Chang Hak YOO
;
Seoung Wan CHAE
Author Information
- Publication Type:Original Article
- From:Journal of Gastric Cancer 2026;26(2):247-259
- CountryRepublic of Korea
- Language:English
-
Abstract:
Purpose:Although gastric cancer (GC) exhibits significant genomic heterogeneity, the clinical implications of its immune microenvironment remain poorly understood.
Materials and Methods:We retrospectively evaluated patients with GC who underwent gastrectomies between 2011 and 2014. The tumors were analyzed for Epstein–Barr virus (EBV), microsatellite instability-high (MSI-H), tumor-infiltrating lymphocytes (CD3), tumor-associated macrophages (CD68 and CD163), and programmed death-ligand 1 (PD-L1) expression. Tumors were classified using the modified The Cancer Genome Atlas scheme, and their clinical characteristics were compared.
Results:A total of 567 patients were classified into EBV (6%), MSI-H (10%), chromosomal instability-like (36%), and genomically stable-like (48%) subtypes. EBV tumors exhibited the highest PD-L1 expression (85%) and immune infiltration by CD3+ T cells (86%), CD68+ macrophages (58%), and CD163+ macrophages (40%). High CD68+ macrophage tumors were associated with advanced stages and worse 5-year disease-free survival (83% vs. 95%; P<0.001);however, this association was not independently significant after adjusting for the tumor-nodemetastasis stage. PD-L1 expression did not significantly affect the survival outcomes.
Conclusions:GC subtypes have distinct immune microenvironments that influence prognosis. Our findings highlight the prognostic and therapeutic potential of immune profiling in GC.
