Stage-aware programmed death ligand 1 assessment in gastric cancer: Implications for perioperative immunotherapy

Table 1 Stage-specific immune microenvironment and programmed death ligand 1 interpretation in gastric cancer

Feature1	Stage II	Stage III	Implication for PD-L1 interpretation
CD8+ T-cell function	Functional/high	Exhausted/Low	In stage II, PD-L1 may reflect basal immune regulation; in stage III, PD-L1 indicates immune escape potential
MDSC infiltration	Low	High	Higher immunosuppression in stage III amplifies PD-L1-mediated immune evasion
M2 macrophages	Low	High	Suppressive macrophages in stage III contribute to T-cell inhibition
Cancer-associated fibroblasts	Moderate	High	Dense stroma in stage III limits immune infiltration, enhancing PD-L1 functional impact
PD-L1 expression	Baseline/moderate	Adaptive upregulation/high	PD-L1’s prognostic and predictive relevance is stage-dependent
Spatial heterogeneity	Low-moderate	High	Stage III tumors show more intratumoral variation in PD-L1 and immune cells
T-cell exhaustion markers	Low	High	Correlates with functional impairment of anti-tumor immunity in stage III

¹Comparison of CD8+ T-cell function, myeloid-derived suppressor cell and M2 macrophage infiltration, cancer-associated fibroblast density, programmed death ligand 1 expression levels, spatial heterogeneity, and T-cell exhaustion markers between stage II and III tumors. These features collectively illustrate the stage-dependent prognostic and predictive significance of programmed death ligand 1.

MDSC: Myeloid-derived suppressor cell; PD-L1: Programmed death ligand 1.