Cognitive alterations and brain functional changes following chemotherapy treatment in breast cancer patients: A systematic review on resting-state fMRI studies.

Cognitive dysfunctions and functional brain modifications are among the side effects reported by breast cancer patients that persist beyond the chemotherapy. This paper aims at synthesizing the evidence on cognitive and functional brain changes and their associations in breast cancer patients treated with chemotherapy. A systematic literature search was performed using PubMed, Ovid MEDLINE, Scopus, and Embase up to July 2022. Eligible studies evaluated adult women with breast cancer treated with systemic chemotherapy, that performed cognitive assessment and resting-state functional MRI. Methodological quality was assessed. Sixteen studies were included, with a total of 1054 female participants. All studies reported alterations mainly concerned the fronto-parieto-temporal system and specifically involved the disruption of the DMN. Consistent with these findings, BCPs showed changes in cognitive performance reporting dysfunctions in executive ability, memory, and attention. However, not all the studies found a significant association between functional brain alterations and cognitive dysfunction. Some limitations including lack of sample homogeneity and different methodological approaches were reported. This work highlighted the presence of cognitive dysfunctions and functional brain alteration in breast cancer patients treated with chemotherapy. This allows a greater awareness of the side effects, promoting better clinical management. However, further research is needed to investigate the cause-effect relationship between cognitive and functional alterations.