Older news items (pre-2010) brought over from the old website
Helping 'chemobrain'
Mouse study points to possible treatment for chemobrain
A mouse study has found that four commonly used chemotherapy drugs disrupt neurogenesis, and that the condition could be partially reversed with the growth hormone IGF-1. Surprising the researchers, both the drugs which cross the blood-brain barrier (cyclophosphamide and fluorouracil) and the two that don’t (paclitaxel and doxorubicin) reduced neurogenesis, with fluorouracil producing a 15.4% reduction, compared to 22.4% with doxorubicin, 30.5% with cyclophosphamide, 36% with paclitaxel. A second study of a single high dose of cyclophosphamide, a mainstay of breast cancer treatment, resulted in a 40.9% reduction. Administration of the experimental growth hormone IGF-1 helped in all cases, but was more effective with the high dose.
[ibib]448[/ibib]
http://www.eurekalert.org/pub_releases/2009-12/uorm-usr121709.php
Stem cells restore cognitive abilities impaired by brain tumor treatment
A rat study has found that transplanted stem cells restored learning and memory to normal levels four months after radiotherapy. This compares with a greater than 50% decline in cognitive function in those rats that didn’t receive the therapy. Cranial irradiation is a common treatment for brain tumors.
[ibib]803[/ibib]
http://www.eurekalert.org/pub_releases/2009-11/uoc--scr110509.php
Exercise can aid recovery after brain radiation
A mouse study has found that exercise can prevent a decline in memory after whole-brain radiation treatment. Mice that had radiation plus access to a running wheel did as well at remembering where an escape hole in maze was as normal mice that didn't exercise. Irradiated mice that had no access to an exercise wheel eventually showed no particular preference for the section of the maze with the escape hole. The irradiated mice who didn’t exercise also showed depressive-like behavior, while those who exercised did not.
Wong-Goodrich, S.J. et al. 2009. Exercise promotes recovery from cognitive dysfunction, depressive-like behavior, and loss of hippocampal neurogenesis following whole-brain irradiation in adult mice. Presented October 20 at the annual Society for Neuroscience meeting in Chicago.
http://www.eurekalert.org/pub_releases/2009-10/dumc-eca101309.php
Potential remedy for the 'mental fog' in cancer patients
A rat study has found that injections of the antioxidant N-acetyl cysteine (a modified form of the dietary amino acid cysteine), fully prevented the memory loss induced by the commonly used chemotherapy drugs adriamycin and cyclophosphamide. The findings suggest that the cause of impairment is oxidative stress. More research will be needed to determine the safety of NAC for chemotherapy patients.
[ibib]846[/ibib]
http://www.eurekalert.org/pub_releases/2008-09/s-prf090408.php
Anastrozole does not impair cognition in postmenopausal women at risk of breast cancer
Trials have demonstrated that anastrozole is superior to tamoxifen in preventing breast cancer recurrence, and contralateral breast cancer in postmenopausal women, however other research has suggested that women receiving endocrine therapies show significantly poorer performance on verbal memory and processing tasks. In a substudy of the International Breast Intervention Study (IBIS II), which was specifically designed to investigate the clinical benefit of anastrozole, given daily for 5 years, as a primary chemopreventive treatment, cognitive function was assessed at baseline and at 6 and 24 months after the start of treatment. There were no significant differences between the anastrozole group and the placebo group in attention or memory, however, at 24 months significantly more women in the anastrozole group reported hot flushes. I note the recent study indicating the number of hot flushes in postmenopausal women is correlated with cognitive impairment.
[ibib]640[/ibib]
http://www.eurekalert.org/pub_releases/2008-09/l-adn082908.php
Narcolepsy drug alleviates post-chemotherapy fogginess
A trial involving 68 breast cancer survivors suffering from ‘chemo-brain’ has had positive results with modafinil (Provigil), a drug that promotes wakefulness. The women who took modafinil for eight weeks reported major improvements in memory, concentration and learning.
The findings were presented on June 3 at the American Society of Clinical Oncology meeting in Chicago.
http://www.eurekalert.org/pub_releases/2007-06/uorm-bpa052207.php
Diabetes drug shows promise for preventing brain injury from radiation therapy
Hope for preventing the memory and learning problems that cancer patients often experience after whole-brain radiation treatments comes from a rat study. Rats receiving the diabetes drug piolitazone (Actos®) before, during and after radiation treatments did not experience cognitive impairment. The drug is thought to work by preventing inflammation.
[ibib]1156[/ibib]
Full text available at http://tinyurl.com/37xglp
http://www.eurekalert.org/pub_releases/2007-01/wfub-dds011007.php
Possible treatment found for 'chemobrain'
A common consequence of chemotherapy is memory problems, confusion and difficulty in concentrating ("chemobrain"). While nearly all breast and ovarian cancer patients receiving chemotherapy or radiation treatments seem to suffer chemobrain, 61% continue to experience memory problems long after their cancer treatment has stopped. A new study involving 154 cancer survivors suggests a possible new treatment using the drug dexmethyphenidate (d-MPH). The drug significantly reduced fatigue and improved memory.
Results of the study were presented to the annual meeting of the American Society of Clinical Oncology.
http://www.eurekalert.org/pub_releases/2005-06/uoc-ptf060705.php
Estrogen boosts memory in men with prostate cancer
A new study suggests that high doses of estrogen may improve long-term memory and decrease feelings of confusion in men whose testosterone levels have been lowered to treat advanced prostate cancer. The findings suggest that hormone deprivation, prostate cancer or a combination of the two significantly impair verbal memory, while estrogen therapy significantly improves verbal memory performance. Hormone deprivation appears to slow working memory performance, but did not affect accuracy. Supplementation with estrogen did not affect working memory.
Beer, T.M. & Janowsky, J. 2004. High dose estrogen may enhance memory in men with prostate cancer. Presented at the American Society for Clinical Oncology annual meeting in New Orleans, La. on June 6.
http://www.eurekalert.org/pub_releases/2004-06/ohs-ebm060604.php
Evidence for 'chemobrain'
Childhood brain tumors permanently impact cognition & lifestyle
A survey involving 785 CNS cancer survivors, 5,870 survivors of non-CNS cancers (such as leukemia, Hodgkin's disease, and bone tumors), and 379 siblings of CNS cancer survivors, sent at least 16 years after diagnosis, has found that CNS cancer survivors reported significantly greater neurocognitive dysfunction than their siblings and survivors of other types of cancer. Moreover, these problems were linked to lower achievement in education and in full-time employment and income, as well as less chance of being married. The worst problems were found in those who had tumors in the cortex, and those who had cranial radiation treatment.
Ellenberg, L. et al. 2009. Neurocognitive Status in Long-Term Survivors of Childhood CNS Malignancies: A Report From the Childhood Cancer Survivor Study. Neuropsychology, 23 (6), 705-717.
Full text available at http://www.apa.org/journals/releases/neu-23-6-705.pdf
http://www.eurekalert.org/pub_releases/2009-11/apa-bti102709.php
Whole-brain radiation therapy for tumors results in worse cognitive function
In a randomised controlled trial, 58 patients with one to three brain tumors were treated either with stereotactic radiosurgery (SRS) plus whole-brain radiotherapy (WBRT), or with SRS alone. Those who were randomly assigned to SRS plus WBRT were more likely to show a significant drop on a verbal learning & memory test at 4 months than patients randomly assigned to SRS alone (52% vs 24%, despite patients in the SRS alone group having a higher overall brain tumour recurrence rate. This finding persisted at 6-month follow-up. However, tumors didn’t recur in 73% of patients in the SRS plus WBRT group at 1 year, compared with 27% of patients who received SRS alone. Mortality rates were also higher in the SRS alone group. Despite this, the authors advise against WBRT because it causes more of decline in brain function — but point to the need for close clinical monitoring in that case (but see report below).
[ibib]1211[/ibib]
Full Article at: http://press.thelancet.com/tlowbrt.pdf
http://www.eurekalert.org/pub_releases/2009-10/l-aow100109.php
http://www.eurekalert.org/pub_releases/2009-10/uotm-srp100509.php
Increased risk of cognitive problems for brain cancer patients who have whole brain radiation
A six-year study of 58 cancer patients with tumors that have spread to the brain has found that those who had whole brain radiation as well as stereotactic radiosurgery (SRS) had more than double the risk of developing learning and memory problems compared to those who only had stereotactic radiosurgery. The trial was halted when interim results showed that patients who received both had a 49% decline in learning and memory functioning at four months, while those who underwent stereotactic radiosurgery alone experienced only a 23% decline in neurocognitive functioning. Nearly half of the patients who had both treatments lost the ability to recall five words from the same list over three attempts.
The study was presented September 22, 2008, at the American Society for Therapeutic Radiology and Oncology's 50th Annual Meeting in Boston.
http://www.eurekalert.org/pub_releases/2008-09/asft-cpe091508.php
Chemotherapy may not affect memory in breast cancer patients
A study that tested 30 women with breast cancer repeatedly before each cycle of chemotherapy and one month after the final cycle, comparing them to healthy controls, found the women with breast cancer had slight problems in attention and learning skills before chemotherapy started. Only three women (10%) developed cognitive problems during chemotherapy, and interestingly, these were not the women who reported that they had problems.
Another study compared 40 women with breast cancer not yet treated, 27 women who had recently had a breast biopsy that was not cancerous, and 20 breast cancer survivors who had completed treatment at least one year before. 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, but both groups were slower and less accurate than the breast cancer survivors. The results suggest the cognitive difficulties may be related to stress as a result of the diagnosis and other quality-of-life factors.
The studies were presented at the American Academy of Neurology Annual Meeting in Chicago, April 12–19.
http://www.eurekalert.org/pub_releases/2008-04/aaon-cmn040208.php
Chemotherapy's damage to the brain identified
On the other hand, studies have shown that upwards of 82% of breast cancer patients report that they suffer from some form of cognitive impairment, and that a significant proportion of these (reports range from 15-20% to 50%) have lingering cognitive problems a year or more after treatment. And following their demonstration that three common chemotherapy drugs used to treat a wide range of cancers are more toxic to healthy brain cells than the cancer cells they were intended to treat, researchers have now found in cell and mouse studies that the widely used chemotherapy drug 5-fluorouracil (5-FU) is associated with a progressing collapse of support cells that are responsible for producing myelin. The next step will be to find out why some patients are vulnerable to this, and others not.
[ibib]935[/ibib]
Full text available at http://jbiol.com/content/7/4/12
http://www.eurekalert.org/pub_releases/2008-04/uorm-rdc041708.php
Cognitive deficits among cancer patients insufficiently recognized problem
A survey of 471 cancer patients has found that the cognitive impairment experienced by 14 to 45% of cancer patients can be long-lasting and severely affect their personal and professional lives. Patients report that the lack of concentration, short-term memory loss, difficulty with word recall and the inability to organize or multi-task have led to significant problems at home and in the workplace. 42% described their doctors as dismissive or indifferent when it came to addressing their concerns.
To view the executive summary, visit www.hurricanevoices.org/today/cognition.
http://www.eurekalert.org/pub_releases/2007-10/hvbc-cdl100107.php
How whole-brain radiation might cause dementia
Whole-brain radiation is widely used to treat recurrent brain tumors as well as to prevent other cancers from spreading to the brain. About a half of patients later develop progressive memory problems. A new study has now identified changes in brain chemistry that may be responsible. Using middle-aged rats, researchers found changes in brain receptors for the neurotransmitter glutamate. The changes may impair synaptic communication.
The research was reported at the annual meeting of the Radiation Research Society in Philadelphia.
http://www.eurekalert.org/pub_releases/2006-11/wfub-ssp103006.php
Common cancer treatments toxic to healthy brain cells
A new study may explain ‘chemo-brain’ (cognitive dysfunction following chemotherapy). The study reveals that common drugs used to treat cancer are far more toxic to healthy brain cells than cancer cells — typical exposure levels killed 70-100% of brain cells but just 40-80% of the cancer cells. Moreover, the healthy cells continued to die for at least six weeks after treatment. Now the task is to find out how to protect healthy cells from the drugs.
The full article is available at: http://jbiol.com/content/5/7/22
[ibib]568[/ibib]
http://www.eurekalert.org/pub_releases/2006-11/uorm-cct112806.php
Chemotherapy temporarily affects the brain
A new study has found that although significant regions of the brain associated with cognitive function were significantly smaller in breast cancer patients within 12 months of receiving adjuvant chemotherapy, after three years, there were no differences in these regions between those who had received chemotherapy and those who had not.
[ibib]418[/ibib]
http://www.eurekalert.org/pub_releases/2006-11/jws-cta112006.php
Chemo drugs for treating breast cancer may cause changes in cognitive function
A study involving female mice confirms the existence of "chemobrain", finding mild to moderate learning and memory deficits in mice receiving methotrexate and 5-fluorouracil (5FU), two drugs widely used in women to prevent recurrence of breast cancer. The deficits extended only to those types of memory that involve the hippocampus or the frontal lobes (spatial memory and working memory, in this instance). The study only looked at short-term effects (2—4 weeks).
[ibib]1069[/ibib]
http://www.eurekalert.org/pub_releases/2006-10/b-cdf102706.php
Brain scans reveal 'chemobrain' no figment of the imagination
A PET study of 21 women who had undergone surgery to remove breast tumors five to 10 years earlier found that the 16 who had been treated with chemotherapy regimens near the time of their surgeries to reduce the risk of cancer recurrence had specific alterations in activity of frontal cortex, cerebellum, and basal ganglia compared to 5 breast cancer patients who underwent surgery only, and 13 control subjects who did not have breast cancer or chemotherapy. The alterations suggested the chemotherapy patients’ brains were working harder to recall the same information.
[ibib]542[/ibib]
http://www.eurekalert.org/pub_releases/2006-10/uoc--bn092906.php
Cancer survivors may be at higher risk for cognitive dysfunction
A study involving 702 cancer survivors and their cancer-free twins has found that cancer survivors are twice as likely to develop cognitive problems as individuals who have never been treated for cancer. About 15% of the cancer survivors showed cognitive dysfunction. The study did not involve patients who had tumors involving the central nervous system. A follow-up study is planned, to compare those who received different treatments for their cancer.
[ibib]284[/ibib]
http://www.eurekalert.org/pub_releases/2005-05/uosc-csm052705.php
Impaired neuromotor function following cancer treatment can improve
A study of 142 patients who had blood disorders and who underwent hematopoietic cell transplant (preceded by high-dose chemotherapy) found that, at three months after transplant, patients experienced a significant decline in all cognitive and motor functions tested. By one year, however, the neuromotor functions for most patients had come back to the level experienced before the transplant, with the exception of two capabilities: grip strength and motor dexterity. Patients who had no chemotherapy or chemotherapy with only hydroxyurea prior to the transplant and those who did not receive certain immune suppressants were better off.
Syrjala, K.L., Dikmen, S., Langer, S.L., Roth-Roemer, S. & Abrams, J.R. 2004. Neuropsychologic changes from before transplantation to 1 year in patients receiving myeloablative allogeneic hematopoietic cell transplant. Blood, 104, 3386-3392.
http://www.eurekalert.org/pub_releases/2004-11/asoh-inf110804.php
New radiation therapy of brain tumors in children spares cognitive functions
The second phase of a clinical trial for ependymoma (a malignant brain tumor that occurs predominately in children) suggests a radiation therapy technique called conformal radiation therapy (CRT) allows young patients to enjoy normal development of their cognitive functions. About 75% of the 88 children treated for ependymoma with CRT did not experience progression of their cancer after three years, and their cognitive development was not significantly impaired by radiation therapy. Although radiation treatment is more effective than chemotherapy for brain tumors, physicians have been reluctant to use it because of fears of impairing cognitive development in young children.
[ibib]637[/ibib]
http://www.eurekalert.org/pub_releases/2004-08/sjcr-3io080504.php
Cognitive dysfunction found in women with breast cancer prior to treatment
The first study to evaluate cognitive skills prior to chemotherapy has found significant deficits in neuropsychological function in breast cancer patients before undergoing chemotherapy, and suggests the incidence of "chemobrain," a widely reported side effect in women undergoing treatment for breast cancer, may be overestimated. The study found 35% of the women demonstrated baseline cognitive impairment with significant deficits in verbal learning and memory prior to chemotherapy. Psychomotor processing speed and attention, non-verbal memory, naming, complex visual tasks and hand fine motor dexterity also trended toward significant impairment compared to the controls.
[ibib]544 [/ibib]
http://www.eurekalert.org/pub_releases/2004-06/jws-scw061604.php