Indiana University
School of Medicine News
September 29, 2010
The cognitive effects of chemotherapy, often referred to as "chemobrain,"
have been known for years. However, the IU research is the first to use brain
imaging to study women with breast cancer before and after treatment, showing
that chemotherapy can affect gray matter. The researchers reported their
findings in the October 2010 edition of Breast Cancer Research and
Treatment.
"This is the first prospective study," said Andrew Saykin, Psy.D., director of
the Indiana
University Center for Neuroimaging and a researcher at the
IU Simon Cancer Center. "These
analyses, led by Brenna McDonald, suggest an anatomic basis for the cognitive
complaints and performance changes seen in patients. Memory and executive
functions like multi-tasking and processing speed are the most typically
affected functions and these are handled by the brain regions where we
detected gray matter changes."
Dr. Saykin, who is Raymond C. Beeler Professor of Radiology at the IU
School of Medicine, and colleagues
studied structural MRI scans of the brain obtained on breast cancer patients
and healthy controls. The scans were taken after surgery, but before radiation
or chemotherapy, to give the researchers a baseline. Scans were then repeated
one month and one year after chemotherapy was completed.
The researchers found gray matter changes were most prominent in the areas of
the brain that are consistent with cognitive dysfunction during and shortly
after chemotherapy. Gray matter density in most women improved a year after
chemotherapy ended.
For many patients, Dr. Saykin said, the effects are subtle. However, they can
be more pronounced for others. Although relatively rare, some patients --
often middle-aged women -- are so affected that they are never able to return
to work. More commonly, women will still be able to work and multi-task, but
it may be more difficult to do so.
The study focused on 17 breast cancer patients treated with chemotherapy after
surgery, 12 women with breast cancer who did not undergo chemotherapy after
surgery, and 18 women without breast cancer.
"We hope there will be more prospective studies to follow so that the cause
of these changes in cancer patients can be better understood," Dr. Saykin
said.
Dr. Saykin and his colleagues started their research at Dartmouth Medical
School before finishing the data analyses at IU. A new, independent sample is
now being studied at the IU Simon Cancer Center to replicate and further
investigate this problem affecting many cancer patients.
Other researchers included lead author Brenna McDonald, Psy.D., M.B.A.,
assistant professor, Department of Radiology and Imaging Sciences, IU School
of Medicine; Susan Conroy, M.D., Ph.D. student; Tim Ahles, Ph.D., professor of
psychiatry, Memorial Sloan-Kettering Cancer Center, N.Y.; and John West, M.S.,
an imaging researcher at the IU Center for Neuroimaging.
The study was supported by a grant from the Office of Cancer Survivorship of the National Cancer Institute, National Institutes of Health and the Indiana Economic Development Corp.
http://communications.medicine.iu.edu/newsroom/stories/2010/iu-researchers-chemotherapy-alters-brain-tissue-in-breast-cancer/