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Investigating "Chemo Fog"

Tuesday, January 27th, 2009

A team of Temple University researchers just received a 1.5 million dollar grant from the National Institutes of Health to study something cancer patients and doctors refer to as chemo fog, or chemo brain – Maiken Scott reports:


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Additional Interview:

Maiken also spoke with Dr. Pamela Shapiro, a congitive psychologist at Fox Chase Cancer Center who studies the impact of chemo therapy on breast cancer patients. Here is her interview:


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Transcript of radio report:

31 year old Eva Cruz has tears in her eyes as she recalls losing her beautiful black hair after two sessions of chemo therapy last year – but she worries that chemo caused her to lose something else as well – her memory:

Cruz: My doctor had asked me if… if I was forgetting things and I said, YEAH, you know..

Cruz is cancer-free since finishing chemo in August of last year but she says her memory problems haven’t gotten better, instead, they feel worse.

Cruz: I have to write down now what I do the date of what I’m doing, that day, the day before, I have to put everything down so I can remember what I did.

Many cancer patients report feeling “fuzzy”, “slowed down” or forgetful, sometimes for months and years after chemo is completed. But the causes are not yet understood. Researching the impact of chemo on the brain is increasingly important as people are surviving longer and cancer treatments are becoming more successful:

Walker: You have to survive your cancer to be concerned about cognitive deficits.

Temple University Researcher Ellen Walker is investigating the direct effects of chemo medications on the brain in mice. She says when looking at this issue in humans, many factors are at play:

Walker: Is it the stress of cancer, is it the disease itself, does the tumor have factors that are causing forgetfulness, anemia, there’s also secondary effects from chemotherapy especially in women, it can kind of catapult them into menopause.

The mice in Walker’s study are given a dose of chemotherapy, and then asked to learn a complex task. They usually learn the task quickly on day one, but on day two changes are evident:

Walker: What we are finding with a couple of the chemo-therapeutic agents we have looked at is on day two, the animals have a difficult time recalling what they learned. it is as if they didn’t really learn it.

Crystal Denlinger is a medical oncologist at Fox Chase Cancer Center in Philadelphia. She says given the many side effects of chemo; nausea, fatigue, hair loss, her patients mention diminished cognitive function more as an afterthought.

Denlinger: They will come with their questions and they’ll pull out their books and sort of offhandedly say ‘oh, my chemo brain is in effect right now so I need to write my questions down’

Denlinger says that in the future, research like the study Walker is doing could inform her choice of treatment for a patient.

Denlinger: Trying to figure out if there are certain drugs that are more toxic vs less toxic, and if we can utilize those drugs, but more importantly, what are interventions that we can do to minimize any cognitive impairment.

Temple University’s Ellen Walker says interventions to minimize chemo fog could be a next step in her research.


  • Dickey says:

    I am in my 3rd year of Tamoxfin. I forget to close my door at home and do not think of dinner until the fire alarm goes off. I am in a fog with long termed memory but also I feel I have new brain growth or rather. I am using new cells. I understand differently. I problem solve differently. I have different goals and ideas I didn’t know before. I am like a reincarnated person with vague memory of an old past life. I read that the chemo caused DNA changes. Tell me more.

  • Jan Pearson says:

    I’ve been on an oral cancer agent, Sprycel, for a little over 2 years, and I’ve steadily been going downhill mentally. I’m alarmed and panicked by it as I’ve already been demoted at work and fear that I’m going to be terminated. I have all teh classic symptoms and have been complaining about it for 2 years. It was obvious from the start. I use to be that I could multi-task, had great bookkeeping/math skills, loved the stress of deadlines, and now I can barely function. I have a hard time comprehending what I’ve just read and have to reread it over and over again. I forget how to do simple tasks I use to do without thinking. I’d love to participate in any study that might help, but more than anything I NEED HELP! If I lose my job because of my brain, then I lose my medical insurance and drug coverage. I’m in a catch-22 situation and need help!

    Please hurry.

  • lydia taylor says:

    My son was diagnosed with adenocarcinoma in November 2008, after receiving Chemo he also experienced memory loss. Please keep us updated about your research.

  • Emma Browning says:

    Very interested in this study as it has been three years since I finished Chemo and I have recently been having episodes of what seems to be the Chemo fog I experienced while having Chemo and for a while afterwards. Is there a way that I can receive updates?

  • During and since my chemo treatments, my memory capability has diminished. However, I was noticing a minimal loss before my illness or chemo/radiation as I aged. I am now 81. The loss … or ‘fog’ … increased during and after the chemo. I am back to a somewhat reduced gym regimen and am more active socially again and I notice that the more active I become, the less extreme the ‘fog’ seems.

  • Jill Curtis says:

    So happy this is being researched, cos since doing chemo last year my memory is very bad, and its hard to know you lost not only chunks of your life whether is be minutes or hours, but that during day to day activities it could end up being dangerous if you forget things like turning the stove off, or getting out of the car without turning it off (I have done both).
    You need any further information please contact me at the above email.
    Good luck with the research
    Jill Curtis – Survivor of Colon Cancer (stage III with a reoccurance).

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