Sorry if this is old news

[Tom]

http://www.oncolink.com/resources/article.cfm?c=3&s=8&ss=23&Year=2006&Month=11&id=13706

Chemotherapy temporarily alters brain structure, which may explain "chemobrain"
Megan Rauscher
Reuters Health
Posting Date: November 27, 2006

Last Updated: 2006-11-27 11:31:21 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Adjuvant chemotherapy causes transient structural changes in cognitively sensitive areas of the brain, which may partly account for some of the previously reported cognitive difficulties referred to as "chemobrain," Japanese investigators report in the January 1, 2007 issue of Cancer, published online November 27.

The neural mechanisms responsible for cognitive impairments related to chemotherapy have not been fully elucidated, Dr. Masatoshi Inagaki, of the National Cancer Center Hospital East in Chiba and colleagues note in the report.

"Our study explored the regional brain volume differences between breast cancer survivors exposed to adjuvant chemotherapy and those unexposed, using brain MRI within 1 year and 3 years after their cancer surgery," Dr. Inagaki told Reuters Health.

Among 105 women who participated in the 1-year study, 51 received adjuvant chemotherapy and 54 did not. Among the 132 women in the 3-year study, 73 received adjuvant chemotherapy and 59 did not.

Within 1 year of cancer surgery, investigators observed that women exposed to adjuvant chemotherapy had smaller regional volumes of gray and white matter than unexposed women. The brain regions affected included the prefrontal, parahippocampal, cingulate gyrus, and precuneus regions.

However, at 3-years post-surgery, there were no regional brain volume differences between chemotherapy exposed and unexposed women.

[Tom]

"These results lead to the idea that adjuvant chemotherapy could have a temporary effect on brain structure, which would recover 3 years after the cancer surgery," Dr. Inagaki said.

In this study, the researcher added, "comparisons of memory functions did not show significant differences" between chemotherapy exposed and unexposed women. "Even within 1 year from surgery, no clinical symptoms, including memory deficits, were observed in the present study," Dr. Inagaki said.

A "more detailed, longitudinal controlled study with a large sample" is needed to confirm the current results, Dr. Inagaki concluded. "If confirmed, the results can provide new insights to future research to improve the quality of life of cancer patients receiving adjuvant chemotherapy."

Cancer 2007.

[Lani]

I repeat my comments here:
Good news--apparently improves with time
Bad news--study done for CMF chemo, not AC/T, TCH or other herceptin-including regimens

[heblaj01]

An other research paper posted earlier appears to show much longer lasting side effects on brain from chemo:

http://www.ncbi.nlm.nih.gov/entrez/...l=pubmed_docsum (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=17009108&query_hl=1&itool=pubmed_docsum)

Altered frontocortical, cerebellar, and basal ganglia activity in adjuvant-treated breast cancer survivors 5-10 years after chemotherapy.
Breast Cancer Res Treat. 2006 Sep 29
Both Tom's post & the one above should perhaps change the perspective of some MD's who assign most loss of cognitive functions (such as memory deficits) to the temporary anemia resulting from chemo. At least that was the gist of an explanation at a recent public chat room session at the Breastcancer org

[heblaj01]

In this article chemotherapy drugs – carmustine, cisplatin, and cytosine arabinoside are shown to be very poorly selective in killing cancer cells as opposed to normal brain cells. An explanation of the cause of brain damage is found.

http://www.eurekalert.org/pub_releases/2006-11/bc-ccb112406.php
Chemotherapy can be more toxic to brain cells than to cancer cells and may cause brain damage (http://www.eurekalert.org/pub_releases/2006-11/bc-ccb112406.php)