Chronic psychosocial stress: a role in breast cancer etiology?

By
Roar Fosse
Cathrine Behr
May 14, 2026

Frontiers In Oncology

Overview

This report reviews the evidence surrounding chronic psychosocial stress and its potential role in breast cancer development. Preclinical studies suggest a significant link, while epidemiological research shows inconsistent associations, primarily focusing on acute stressors.

Background

Breast cancer remains a leading global health issue, with psychosocial stress being a potential risk factor under investigation. Despite extensive research, the relationship between chronic psychosocial stress and breast cancer remains poorly defined in epidemiological studies, which often emphasize acute stressors. Understanding this relationship is crucial for developing effective prevention and intervention strategies.

Data Highlights

Systematic literature searches identified 29 rodent studies, with 25 indicating that chronic psychosocial stress increased mammary tumorigenesis and/or metastasis.

Key Findings

Chronic psychosocial stress is linked to increased mammary tumorigenesis in 25 out of 29 preclinical rodent studies.
Epidemiological studies predominantly focus on short-lasting adverse life events, showing no consistent association with breast cancer.
There is a need for future epidemiological studies to prioritize chronic psychosocial stress in breast cancer research.
High levels of circulating estrogens may interact with stress responses to increase breast cancer risk.
Current guidelines do not recognize chronic psychosocial stress as a causal risk factor for breast cancer.

Clinical Implications

Healthcare professionals should consider the potential impact of chronic psychosocial stress on breast cancer risk when assessing patients. Future research should incorporate chronic stress assessments to better understand its role in breast cancer etiology and inform prevention strategies.

Conclusion

The evidence suggests that chronic psychosocial stress may be a relevant factor in breast cancer development, warranting further investigation in epidemiological studies. A comprehensive approach that includes both chronic and acute stressors is essential for understanding their combined effects on breast cancer risk.