Tumor-associated macrophages in gastric cancer: Phenotypic plasticity and therapeutic targets

Tumor-associated macrophages (TAMs) are abundant, functionally plastic cells within the gastric cancer tumor microenvironment and influence tumor growth, invasion, metastasis, angiogenesis, immune evasion, chemoresistance, and metabolic reprogramming.The M1/M2 dichotomy incompletely describes TAM states; singlecell and spatial transcriptomic studies have identified specialized populations that vary with tumor subtype, anatomical niche, and disease stage.This review synthesizes current evidence on TAM origin, recruitment, adaptation, and roles in malignant progression, and examines TAM-directed therapeutic strategies.TAM composition and polarization, rather than total macrophage density, may be more relevant to treatment response.Although TAM-targeting approaches show promise in preclinical models, direct clinical targeting in gastric cancer remains limited.Defining subtype-specific TAM states, clarifying microbiota-TAM interactions, and developing predictive biomarkers may advance precision immunotherapy.