I never know whether to be reassured or concerned when I read about evidence for mild chemobrain/cognitive difficulties post cancer treatment. It would be really nice to have a reason for forgetting to buy the milk or to return a phone call, but I fear the real reason is just the usual busy day and packed "to do" lists. Many women report a sense of mental fuzziness during or shortly after chemo, more trouble with word finding and remembering names. It usually improves fairly quickly, but there most of us are a bit less sharp than we were at 25. We can surely blame some of it on reduced (or absent) estrogen, normal aging, and everything we have experienced.
Here is a summary from the Komen Foundation about a recent study at the Moffett Cancer Center in Florida that did support "mild" chemobrain in most women who received adjuvant chemotherapy for breast cancer.
Some Evidence of Mild "Chemo Brain" in Breast Cancer Survivors
Breast cancer patients treated with chemotherapy are at risk for mild cognitive deficits (sometimes referred to as chemo brain) after treatment, according to the results of a study published early online in the Journal of Clinical Oncology.
A large portion of breast cancer patients will ultimately receive adjuvant chemotherapy. Patients undergoing chemotherapy have long complained of a phenomenon referred to as "chemo brain." Chemo brain refers to changes in cognitive function, such as loss of memory and inability to think clearly or perform some daily functions. Thus far, researchers have not been able to pinpoint the cause of chemo brain, but studies are ongoing to evaluate brain structure and function in order to better understand the effects of chemotherapy on the brain.
There is mixed evidence regarding the scope and duration of chemo brain. Many studies have not focused on the post-chemotherapy period and thus have produced little data regarding the long-term effects of chemotherapy on the brain.