"Georgetown's Lombardi Comprehensive Cancer Center announced the launch of a study that examines the effect of chemotherapy on the thoughts and memory of patients ...Another reminder of how much there is yet to learn about the side effects of chemotherapy and other cancer treatment drugs. I have been very conscious of the damage to my memory and other cognitive functions. I've felt some improvements and I hope for more but it's my understanding that I'll not likely gain back all of my lost ground even after factoring in age related effects.
Those with "chemo-brain" may experience loss of memory, often forgetting to complete assignments or failing to remember others' names. This is accompanied by an impaired ability to organize or to focus on a particular subject. Cognitive decay makes ordinary tasks, such as balancing a checkbook or cooking a meal, more difficult for the patient."
If they learn more about chemo-brain, maybe methods will be found to reduce the impact. Of course, the real answer would be to find out what CAUSES cancer in the first place.