Brain Functional and Structural Changes of Breast Cancer After Chemotherapy: A Systematic Review and Meta-analysis

Chemotherapy, a standard treatment for breast cancer (BC), is known to exert neurotoxic effects on the central nervous system. The aim of this study was to identify consistent patterns of brain structural and functional alterations linked to chemotherapy in patients with BC and explore potential clinical correlates, such as age, education, and treatment characteristics. Data from 29 neuroimaging investigations, including structural magnetic resonance imaging (MRI), diffusion tensor imaging, and resting-state functional MRI, were analyzed using a coordinate-based meta-analysis. The results revealed significant gray matter reductions in regions including the orbitofrontal cortex, anterior cingulate cortex, insula, cerebellum, and rolandic operculum, alongside functional hypoactivation in the rolandic operculum and insula, when comparing chemotherapy-treated patients to chemotherapy-naive controls. These findings suggest that chemotherapy primarily affects regions involved in cognitive and emotional regulation. A higher education level may serve as a protective factor, possibly reflecting greater gray matter structural integrity, that mitigates chemotherapy-related neurotoxic effects. This study may offer insights into the underlying neural mechanisms of chemotherapy-related cognitive changes. Further research should investigate treatment-specific effects and long-term outcomes.