Bidirectional relationship between depression and the risk and prognosis of gastric cancer

Gastric cancer (GC) is a highly prevalent and life-threatening malignant tumor worldwide, posing a serious threat to human health. Depression is also highly prevalent among patients with GC. A complex bidirectional relationship exists between the two. A total of 52 articles were included in this study to synthesize the evidence on the association between depression and the risk of GC as well as the prognosis of affected patients. The findings indicated that depression can activate the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis, promote the release of catecholamine neurotransmitters, and influence the proliferation, invasion, and metastasis of GC through signaling pathways such as the β2-adrenergic receptor. Furthermore, the severity of depression is positively correlated with indicators of GC progression. At the same time, GC can induce or aggravate depression through psychological and cognitive factors, social environment interactions, and diverse pathophysiological mechanisms, including tumor biological characteristics, treatment-related damage, and metabolic disorders. These interactions form a vicious cycle. This minireview summarizes the existing evidence and provides a theoretical basis for clinical interventions aimed at improving treatment outcomes and quality of life in patients with GC.