CHICAGO — Women receiving chemotherapy for breast cancer frequently report problems with memory and concentration. However, two new studies, including one from Michigan State University, suggest that the stress of the diagnosis – not the chemotherapy – is the cause of these problems.
The studies were presented at the American Academy of Neurology’s 60th Anniversary Annual Meeting in Chicago.
The study conducted by Michael Boivin, MSU associate professor of neurology and ophthalmology and psychiatry compared three groups of women: 44 women with breast cancer who had not yet received chemotherapy or radiation; 30 women who had recently had a breast biopsy that was benign; and 20 breast cancer survivors who had completed treatment at least one year before.
All of the women were tested on their cognitive abilities and evaluated for anxiety, depression, their overall quality of life and the amount of social support they had.
On tests of working memory and spatial learning, the women recently diagnosed with breast cancer performed about the same as the women with the recent benign biopsy. However, both groups were less accurate than the breast cancer survivors.
In addition, memory and learning ability for the breast cancer women did not significantly change during treatment in comparison to the benign biopsy women; although women receiving chemotherapy did become less attentive on a simple card identification task.
The recently diagnosed women who had better overall quality of life also had better scores on the cognitive tests. Changes in cognitive performance during breast cancer treatment were related to changes in some aspects of quality of life, especially the spiritual and religious support domain.
In the other study, 30 women with breast cancer were given cognitive tests before each cycle of chemotherapy and again one month after the final cycle. They were compared to 30 healthy women who were also tested five times about a month apart.
The women with breast cancer had slight problems in attention and learning skills before chemotherapy started. Chemotherapy resulted in only a minor slowing in thinking speed. Three women, or 10 percent, developed cognitive problems during chemotherapy.
“These results,” Boivin said, “suggest that cognitive difficulties experienced by women with a new breast cancer diagnosis may be related to stress as a result of the diagnosis and other quality-of-life factors, and not simply due to the effects of chemotherapy or radiation.”
“This is an important issue, particularly as survival rates for breast cancer improve,” said David Darby, author of the second study and chief medical officer of CogState Ltd., an Australian company that developed the cognitive tests used in the studies. “People could be making decisions about whether or not to have chemotherapy based on stories they’ve heard about ‘chemofog’ or ‘chemobrain.’ Hopefully this information will help people make informed decisions.
Boivin’s study was supported by the Templeton Advanced Research Program of the Metanexus Institute. Darby’s study was supported by CogState Ltd., the University of Melbourne and the Peter MacCallum Cancer Centre.
The American Academy of Neurology, an association of over 21,000 neurologists and neuroscience professionals, is dedicated to improving patient care through education and research. A neurologist is a doctor with specialized training in diagnosing, treating and managing disorders of the brain and nervous system such as Alzheimer’s disease, epilepsy, multiple sclerosis, Parkinson’s disease and stroke.
For more information about the American Academy of Neurology, visit www.aan.com.
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Michigan State University has been advancing knowledge and transforming lives through innovative teaching, research and outreach for more than 150 years. MSU is known internationally as a major public university with global reach and extraordinary impact. Its 17 degree-granting colleges attract scholars worldwide who are interested in combining education with practical problem solving.