Associação entre marcadores oxidativos e citotóxicos induzidos pela quimioterapia em mulheres com câncer de mama e ocorrência de déficit da função executiva

Abstract

Chemotherapy for breast cancer may lead to undesirable cognitive side effects. Moderate cognitive abnormalities are seen in 15-50% of patients and up to 75% may report subtle changes. This study analyzed the possible association between executive dysfunction and early oxidative biomarkers related to the immediate cytotoxic reaction to chemotherapeutic regimens in a longitudinal, prospective fashion. Executive functions were probed through specific neuropsychological test and analyzed according to RCI criteria. Oxidative and gene expression. biomarkers were analyzed in two consecutive blood samples. Qualitative and quantitative variables were compared through, respectively, Chi-square or Fisher’s exact test, and the Wilcoxon-Mann-Whitney test. The study found that 78% of women with breast cancer undergoing chemotherapy had abnormalities in tests of executive function and these patients had reduced PBMC viability. ROC curves showed that lipoperoxidation (LP) could predict development of executive dysfunction (AUC 0.744). Women with high concentrations of LP (0,1 nmol MDA / mL) had almost 3.5 times the risk to develop executive dysfunction (CI 95%:1,22-9,68), and this association was independent of age, type of chemotherapeutic regimen or scores of depression or anxiety. LP levels had moderate power of prediction of executive dysfunction (p 0.03). Furthermore, level of dsDNA cultivated during 24 hours in CMPS were significantly higher in women with executive dysfunction (p 0.03). The results of the present study open new avenues of evaluation of the risk of cognitive abnormalities, particularly executive dysfunction, through association with oxidative biomarkers.