Breast cancer survivor Laverne, 67, retired pharmaceutical representative, wasn’t sure if her memory problems were attributable to chemotherapy or to normal age-related cognitive decline. “I read that one of the side effects of the chemotherapy was memory loss, but the truth is I had senior moments before, during and after chemo. I can’t definitively say that I noticed a difference,” she laughs.
One day, I put my sneakers in the freezer, blanked out on my sister’s birthday, and received a call from my son’s school because I’d forgotten to pick him up”
– Suzanne, 35, recalls of her memory lapses during chemotherapy treatment for breast cancer.
Suzanne and Laverne were responding to questions about their experiences with chemobrain or chemofog. According to Mayo Clinic, chemobrain “refers to cognitive changes during and after chemotherapy,” which can affect memory, the ability to find words, and the ability to manage multiple tasks and learn new things. The phenomenon affects about 20% to 30% of breast cancer patients who undergo chemotherapy.
Just as Suzanne and Laverne have different views on the subject of chemobrain, so do members of the medical profession. Some say that chemobrain is a real phenomenon associated with chemotherapy and point not only to the significant number of documented chemobrain cases, but also to the pivotal studies that exist on the subject. One study published in the Journal of Clinical Oncology (2000) showed that more patients who had undergone or were undergoing treatment “had moderate or severe cognitive impairment” compared with their “healthy” counterparts. Another study, printed in the Journal of the National Cancer Institute (1998), showed that women who on average had completed treatment two years prior still showed cognitive impairment, suggesting the long-term effect of chemo on the brain.
However, others in the profession are not that certain about chemobrain, and argue that the added stress of chemotherapy to an otherwise busy schedule could have an impact on how a patient functions, as could reduced levels of estrogen, fatigue, anxiety and some of the medications used to mitigate the other side effects of chemotherapy. And a recent study in the journal Cancer (2004) reported that perhaps chemobrain might not be attributed to chemotherapy at all, but to other factors not previously investigated. The study set out to evaluate the cognitive state of 84 women with cancer before undergoing chemotherapy. The results showed that, among other things, 35% of the women “exhibited cognitive impairment” and that “memory function (25%) [was] impaired more frequently relative to normative expectations” even prior to chemotherapy treatment. The study concluded that studies regarding postchemotherapy cognitive impairment must include pre-chemotherapy cognitive evaluations.
Most recently, researchers at UCLA took brain scans of breast cancer survivors, and showed the brains of those who were treated with chemotherapy had to work harder than those of survivors whose treatment was surgical, to perform the same tasks.
While the debate for what causes chemobrain goes on, it’s hard to dispute that many cancer survivors notice changes in their cognition that can be frustrating, or even debilitating.