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    • Graphic text:  seeing through the fog of "chemo brain"

Seeing Through the Fog of “Chemo Brain”


WITH ADVANCES IN TREATMENT OVER THE LAST SEVERAL DECADES, the number of cancer survivors continues to grow – currently estimated at 14 million, and expected to reach 18 million within the next decade. But survivorship can come with a cost. “As more people are cured of their cancer, living with the long-term consequences of cancer treatment has become more of an issue,” says Dr. Patricia Ganz, a Fielding School professor of health policy and management.

A hematologist-oncologist whose pioneering studies helped to bring the issue of cancer patients’ post-treatment quality of life into the mainstream, Ganz has for much of the last two decades focused on the phenomenon known as “chemo brain” – the mental fogginess that can persist indefinitely for some cancer survivors, affecting their ability to concentrate, stay organized, multitask and complete other everyday cognitive functions. Her work has shed light on the biological basis for the lingering cognitive symptoms. “Many doctors had thought it must be related to depression or something else, because they could give the same chemotherapy to 100 people and only 15 or 20 would have trouble,” Ganz says. “But it turns out that some may be more genetically predisposed to these late effects.” Cancer therapies cause inflammation that can affect the functioning of the brain’s neurons, Ganz explains. She and her colleagues have found that certain individuals are more prone to persistent inflammation following treatment – an effect associated with both fatigue and cognitive difficulties.

Through large ongoing clinical trials, Ganz and others are seeking to better understand which patients are most likely to experience these chronic treatment effects. In the meantime, Ganz says, “As oncologists, before we treat our cancer patients with something that is potentially toxic we need to be very sure that they need it.”

Ganz, director of prevention and control research for UCLA’s Jonsson Comprehensive Cancer Center, has also worked with UCLA Semel Institute for Neuroscience and Human Behavior researchers on rehabilitation strategies for breast cancer survivors suffering from post-treatment cognitive difficulties. Led by Ganz, the group recently published a study showing that women in an early-intervention group who were given strategies to help them with their memory and focus reported improvements in their cognitive symptoms and performed better on a battery of neuropsychological tests than women who didn’t receive the early intervention, and that these improvements persisted two months after completion of the rehabilitation program. “It was encouraging that the patients told us that they were doing better and also tested better. They also had improvements in brain wave patterns,” Ganz says.

While continuing to study the biological mechanisms underlying chemo brain in an effort to identify patients at risk and pave the way for new therapies, Ganz also serves as a leading voice on the importance of researchers paying close attention to patient reports about their symptoms. “The message of our work is that patient self-report is reliable and something that can be measured and tracked if you give the right tests,” she says. “Too often in the past, patients’ complaints haven’t been taken seriously. As physicians, one of the most important things we can do is to listen to what our patients tell us.”