Long-term cognitive impairment of breast cancer patients after chemotherapy: A functional MRI study

Background: Chemotherapy, a prominent treatment for breast cancer (BC), can have detrimental side effects on the patient's cognitive functions including the executive function. However, the neurophysiological mechanism of the cognitive impairment remains unclear. Objective: The purpose of this study is to explore long-term chemotherapy-related functional connectivity changes using fMRI and the relationship between the connectivity changes and the executive function impairment in breast cancer patients. Methods: In this study, twenty-three breast cancer patients were treated with chemotherapy and twenty-six healthy subjects were recruited as the healthy control (HC) group. The functional connectivity of anterior cingulate cortex (ACC) was calculated from resting-state fMRI of the BC and control groups. The relationship between the functional connectivity of ACC and the executive function was further analyzed based on the patient' response time of the Stroop Interference Test. Results: The results show that functional connectivity of ACC in the BC group is significantly lower than that in the control group. The correlation analysis within the BC group indicates that the functional connectivity of ACC was significantly correlated with the executive function. Conclusion: These findings provide evidence that the functional connectivity changes might be a pathophysiological basis for long-term chemotherapy-related cognitive dysfunction, along with executive function impairment in breast cancer patients. (C) 2016 Elsevier Ireland Ltd. All rights reserved.