A version of the APOE gene could put some cancer patients at higher risk of cognitive problems after chemotherapy, according to a Journal of Clinical Oncology study. Scientists at Georgetown University examined the cognitive function of older breast cancer patients. A small subset of the over 344 newly diagnosed women who carry one or two copies of the APOE4 gene experienced steady and pronounced cognitive decline after chemo, the study states. Researchers compared hundreds of breast cancer patients aged 60 to 98 before and after treatment to a matched group of cancer-free women.
APOE has long been known as a major risk factor for nonfamilial Alzheimer’s, or sporadic Alzheimer’s. It comes in three variants, known as 2, 3, and 4.
Jeanne Mandelblatt, MD, who co-led the study, said that while her study is too small to lead to any conclusion, if future researchers find similar results, providers might have to start screening patients for the APOE4 gene before discussing treatment options.
The study revealed that for most older breast cancer patients, chemotherapy and hormonal treatments do not have major adverse effects on cognitive function. Those who did experience problems in cognitive function after chemotherapy were the small group who had one or two copies of the APOE4 gene.vulnerable to However, this outcome has not been well studied in older women who have been treated for breast cancer, a group that may be more vulnerable to cognitive problems based on multiple chronic diseases and aging processes.”
While chemotherapy doesn’t cause Alzheimer’s disease, some patients may be at risk for both cancer-related cognitive problems and Alzheimer’s—perhaps through a process of accelerated aging or other shared disease processes.
Mandelblatt stressed that the findings of this study need to be confirmed in future studies that include a larger proportion of patients with the APOE4 gene.