Chemotherapy-Related Cognitive Impairment in Patients with Breast Cancer Based on Functional Assessment and NIRS Analysis

Background: Chemotherapy-related cognitive impairment (CRCI), or "chemobrain," isdefined as a phenomenon of cognitive deficits in cancer patients after chemotherapy and is characterized by deficits in areas of cognition, including memory, attention, speed of processing, and executive function, which seriously affect quality of life. The purpose of this study is to investigate the impact of CRCI in breast cancer (BC) patients in chemotherapy treatment (CT+) or not (CT-) and to analyze their relationship with detectable objective changes in cerebral activity during the execution of a phonological and semantic verbal fluency task (PVF and SVF). Methods: An observational, cross-sectional study was carried out at Badajoz University Hospital (Spain). A total of 180 women with BC were included. We used Cognitive Scale (FACT-Cog) for neuropsychological subjective assessment, obtaining scores of perceived cognitive impairment (PCI), and near-infrared spectroscopy system (NIRS) for neuropsychological objective assessment during a verbal fluency task (PVF and SVF), determining alterations in the prefrontal cortex (PFC) assessed as changes in regional saturation index (rSO(2)). Results: A total of 41.7% percent of the patients in the sample had PCI. CT+ was significantly associated with a worse impact in PCI (X over bar = 50.60 +/- 15.64 vs. (X) over bar = 55.01 +/- 12.10; p = 0.005). Average rSO(2) decreased significantly in CT+ ((X) over bar = 63.30 +/- 8.02 vs. (X) over bar = 67.98 +/- 7.80; p < 0.001), and BC patients showed a significant decrease in PVF and SVF on average (<(X)over bar> = 41.99 +/- 9.52 vs. (X) over bar = 47.03 +/- 9.31, and (X) over bar = 33.43 +/- 11.0 vs. (X) over bar = 36.14 +/- 10.68, respectively; p < 0.001). Conclusions: Our findings suggest that cognitive impairments in the domain of executive functioning exist among patients with BC who received CT. The results corroborate the hypothesis that CT is an important factor in cognitive impairment in patients with BC, which has been demonstrated by both subjective (PCI) and objective (PVF, SVF, and rSO(2)) neuropsychological measures. The combination of doxorubicin, cyclophosphamide, and docetaxel induce cognitive impairment.