Jackie, thank you for providing everyone with this link to a new abstract on chemotherapy and cognitive function:
http://www.ncbi.nlm.nih.gov/pubmed/21600374
The paper is just out (journal: Seminars in Oncology, Vol 38, June 2011). It's titled, "An Update on Cancer and Chemotherapy-Related Cognitive Dysfunction: Current Status."
For those of you interested in the full-text version, I've summarized it. You'll see my own comments in italics.
BTW, two of the paper's authors (Tim Ahles of Sloan-Kettering and Sadhna Kohli of the Mayo Clinic) contributed to "Your Brain After Chemo." A lot of the material here is also in our book, but in greater depth.
Here are the highlights:
1) Up to 75 percent of cancer patients experience some type of cognitive impairment either during or after treatment. This may include problems with attention, memory, executive functioning, etc.
Executive functioning refers to tasks an executive might make, such as planning ahead and making decisions.
2) Cognitive problems have been found to be more severe in people who receive chemotherapy versus those who receive only radiation and surgery.
3) About 35 percent of patients may continue to experience impairment for years.
4) It is important to assess a patient's cognitive functioning prior to treatment to determine the degree of change after treatment.
It wasn't until 2004 that researchers at MD Anderson reported findings of one of the first prospective longitudinal studies to look at those prior-and-after points.
What the researchers found was significant and has changed the way many scientists now design studies.
About 61 percent of the participants showed decline in cognitive functioning after beginning treatment.But here's the thing: Had they not tested the patients prior to treatment, they would have detected a decline in only 46 percent of the participants. That's because several patients scored in the normal range prior to treatment and their post-treatment scores were also normal, just lower.
So they would have missed those subtle changes in IQ, behavior, mood, etc. And that term, "subtle," is really subjective. People who are retired and have fewer demands on them may notice no memory issues at all. But for those of us who run households and/or juggle work and kids and relationships, there's nothing subtle about how issues of memory, multitasking, word retrieval and concentration affect our daily lives.
All this goes to the point that we need more sensitive testing.
5) Scientists need to understand the mechanisms behind this phenomenon. Tools at their disposal include: neuropsychologic testing, brain imaging to look at changes in brain volume and metabolism, and an assessment of biologic factors, such as testing for the body's inflammatory response to cancer and chemotherapy, and looking at a person's genetic predisposition to cognitive problems.
6) Breast cancer patients who are treated with tamoxifen and chemotherapy appear to be more impaired than those treated with chemotherapy alone.
7) Studies have shown that mice treated with chemotherapy suffer memory impairment.
All the best,
Idelle