'Chemo Brain' Real, Not Just Patient’s Imagination
Nov. 29, 2012 (Chicago) -- For cancer patients undergoing chemotherapy who have found their complaints of general mental fogginess and haziness dismissed by their doctors as not being a real medical condition, vindication has arrived.
Using brain imaging, researchers have found physiological evidence of "chemo brain," the problems with memory, concentration, and planning that often plague cancer patients during treatment with chemotherapy drugs.
A combination of positron emission tomography and computed tomography (PET/CT) showed chemotherapy can induce changes in the brain that may affect concentration and memory, says researcher Rachel A. Lagos, DO, a resident in diagnostic radiology at the West Virginia University School of Medicine and West Virginia University Hospitals in Morgantown.
"We were surprised at how obvious the changes were," Lagos says. "Chemo brain phenomenon is more than a feeling. It is a change in brain function observable on PET/CT brain imaging."
Chemo Fog Common
In a 2006 study, University of Rochester researchers found that 82% of 595 people with cancer given chemotherapy reported problems with memory and concentration.
Still, the cause of chemo brain has been difficult to pinpoint, leading some doctors to doubt its existence. Some studies using magnetic resonance imaging (MRI) have found small changes in brain volume after chemotherapy, but no definitive link has been found.
So Lagos and colleagues took a different tactic, using a combination of PET and CT imaging to look for changes in brain metabolism in 128 patients who had undergone chemotherapy for breast cancer.
"PET/CT imaging shows how the brain is using energy. So it gives you an earlier look at regions of the brain that are being affected by chemotherapy, as they start to use less energy. That happens long before you can see structural changes in the brain on MRI," she says.
PET/CT imaging revealed changes in metabolism in brain regions involved in long-term memory, mental agility, decision making, problem solving, and prioritizing.
The findings were presented here at the annual meeting of the Radiological Society of North America.
Chemo Brain: Outside Perspective
"Importantly, the regions of the brain that were affected made sense in terms of the symptoms that patients report," says Max Wintermark, MD, engineering chief of neuroradiology for the University of Virginia.