Effect of chemotherapy on gray matter and brain activation in breast cancer patients: an activation likelihood estimation meta-analysis

Abstract Purpose Utilizing activation likelihood estimation (ALE) meta-analysis to investigate alterations of gray matter (GM) and brain activations in patients with breast cancer treated with chemotherapy. Methods Systematic literature search was performed to identify relevant reports. ALE method was used to assess pooled neuroimaging data obtained from selected reports for both GM alteration via voxel-based morphometry (VBM) analysis and brain activation changes from task-based functional MRI (fMRI). Results There were 9 GM studies and 14 fMRI studies included in this meta-analysis. In ALE analysis of GM studies, GM reduction was noted in right superior frontal gyrus, right declive, right insula, right supramarginal gyrus, right culmen, etc. GM increase was noted in left cingulate gyrus, left lentiform nucleus, right cingulate gyrus, right caudate, left superior frontal gyrus, etc. In ALE analysis of fMRI, hyperactivation clusters included regions in left thalamus, left claustrum, left lentiform nucleus, left inferior frontal gyrus, right inferior frontal gyrus, etc. Hypo-activation clusters included regions in left cingulate gyrus, left precuneus, right fusiform gyrus, left middle temporal gyrus, left cuneus, etc. Conjunction analyses showed only overlapping area with both GM reduction and brain hyperactivation was located in inferior parietal lobule. Conclusion This study identified alterations of GM and task-based brain activation in breast cancer patients treated with chemotherapy. This study contributed to the literature on chemotherapy associated neural correlates of brain changes in breast cancer patients.