I used to be proud of my memory. I could stand in front of a jury and summarize my client’s case for an hour without a note in front of me. Now I often find myself walking into a room and wondering why I went there. I watch Mary Pat’s disappointed look when I confess that I forgot to do something she asked me to do just minutes earlier. I slump my shoulders in frustration when I discover that I missed a dose of my medications. It turns out that I’m not the only one going through this. Up to 75% of cancer patients who receive chemotherapy experience cognitive deficits.
I heard a lecture by Dr. Jeffrey Wefel. He’s a neuropsychologist at M.D. Anderson Cancer Center. He treats cancer patients who suffer from chemo brain. Dr. Wefel said there are several reasons cancer patients suffer from cognitive deficits. First, the body’s inflammatory response to cancer can damage brain cells in the hippocampus. Second, the stress of cancer can cause the body to release hormones that result in a reduction of new brain cells being born in the hippocampus. Third, and most importantly, chemotherapy is often very strong and can sometimes cross the blood/brain barrier and kill newly forming brain cells. As old neurons die off, the baby brain cells are not there to replace the old ones which is why patients often report a delay in the start of chemo brain after their chemotherapy treatments. The busulfan dripped into my veins to kill my bone marrow before my stem cell transplant was derived from World War I mustard gas. It’s no stretch to conclude that a chemical strong enough to kill your bone marrow can also cause damage your brain cells.
Chemo brain is not related to age. It is not related to educational level. It strikes cancer patients from all walks of life.
A functional MRI study of identical twins, one of whom had undergone chemotherapy, showed that the cancer patient had to work much harder to focus his mind on mental tasks than his healthy twin. Studies show that the brains of cancer patients suffer a reduction in gray matter. In other words, we lose brain mass after chemotherapy and cancer treatment.
Interestingly, the work done at M.D. Anderson suggests that some people are genetically more prone to chemo brain than others.
Chemotherapy is not the only source of cognitive deficits in cancer patients. Men who are treated for prostate therapy with androgen deprivation therapy and who have a certain type of gene also suffer from “chemo brain”.
How can we fight chemo brain? Dr. Wefel suggests aerobic exercise, strength training, a low carb Mediterranean diet, moderate to no alcohol, stress management, remaining curious, maintaining social connections, computerized brain training, compensatory strategies, and cognitive therapies.