Cancer-related cognitive impairments in patients receiving adjuvant chemotherapy may be associated with under-recruitment of brain regions involved in working and recognition memory, according to a small study published online ahead of print in Cancer.
Researchers led by Lei Wang, PhD, of the Northwestern University Feinberg School of Medicine in Chicago, Illinois, looked at 15 oncology patients who showed evidence of cognitive impairment according to neuropsychological testing as well as self-reporting after receiving adjuvant chemotherapy. They were matched by age and education with 14 cognitively normal control patients.
Patients were asked to perform a nonverbal n-back working memory and visual recognition task during functional magnetic resonance imaging.
The researchers found that with working memory task, when 1-back and 2-back data were averaged with 0-back data, there was significantly reduced activation in the right dorsolateral prefrontal cortex for oncology patients compared with the control group.
In the recognition task, they also found that oncology patients displayed lower activity of the left-middle hippocampus compared to the control group.
“These results suggest that there is a reduction in neural functional postchemotherapy and corroborate patient-reported cognitive difficulties after cancer treatment, although a direct association was not observed,” the authors concluded.
1. Wang L, Apple AC, Schroeder MP, et al. Reduced prefrontal activation during working and long-term memory tasks and impaired patient-reported cognition among cancer survivors postchemotherapy compared with healthy controls. Cancer [published online ahead of print October 20, 2015]. doi:10.1002/cncr.29737.