Chronic psychological stress and gastric cancer: bidirectional associations, biological mechanisms, and clinical implications-a narrative review.

BACKGROUND AND OBJECTIVE: Gastric cancer (GC) remains one of the major malignancies worldwide, and its development and progression are shaped by the complex interplay of tumor-related, patient-related, and psychosocial factors. Chronic psychological stress, particularly anxiety and depression, may be associated with GC susceptibility, treatment tolerance, survival-related outcomes, and quality of life. This narrative review aims to synthesize current GC-specific evidence on the bidirectional relationship between chronic psychological stress and GC. METHODS: Targeted searches of PubMed, Web of Science, and relevant reference lists were conducted up to February 2026. Search terms included "gastric cancer", "chronic psychological stress", "depression", "anxiety", "psychological distress", "β2-adrenergic receptor", "hypothalamic-pituitary-adrenal axis", "inflammation", "immune escape", "microbiota", "gut-brain axis", and "supportive care". Priority was given to GC-specific clinical, epidemiological, mechanistic, and interventional studies. KEY CONTENT AND FINDINGS: Current evidence suggests a clinically meaningful but still evolving bidirectional association between chronic psychological stress and GC. Anxiety and depression are common in patients with GC and may affect treatment tolerance and survival-related outcomes. Mechanistic studies further suggest that chronic psychological stress may be linked to GC progression through neuroendocrine dysregulation, oxidative-inflammatory amplification, immune escape, hormonal and metabolic remodeling, and microbiota-related pathways. Conversely, GC itself may act as a persistent stressor that aggravates anxiety and depressive symptoms. CONCLUSIONS: Chronic psychological stress should be considered a clinically relevant factor in GC management. Further prospective clinical studies, integrated mechanistic investigations, and multidisciplinary intervention trials are needed to clarify causality and determine whether stress-informed management can improve both psychological and oncologic outcomes.