Prechemotherapy differences in response inhibition in breast cancer patients compared to controls: a functional magnetic resonance imaging study.

Prechemotherapy neuroimaging data are lacking in posttreatment cognitive impairment studies. Breast cancer patients and noncancer controls were scanned prior to chemotherapy during a response inhibition task. Task reaction times and error rates, as well as neuropsychological tests, hospital records, and salivary biomarkers, were investigated, yielding no significant group differences. Significant group differences observed for the functional magnetic resonance imaging (fMRI) data depended on the type of analysis performed, most consistently implicating widespread attenuated activations in patients. The patient group also revealed considerable variability in task-related brain activity. These pretreatment differences highlight the need to understand the effects of confounding variables before considering posttreatment effects. Role of the funding source: The Canadian Breast Cancer Foundation has funded this project. Their contribution was solely financial support.