The American Cancer Society (ACS) has awarded City of Hope’s Sunita Patel, Ph.D., a three-year, $702,000 grant to understand how breast cancer and its treatment may cause thinking problems and fatigue in women.

Sunita Patel is studying the factors behind “chemo brain.” (Photo by Alicia Di Rado)

Patel, a neuropsychologist and assistant professor in the departments of Population Sciences, Pediatrics and Supportive Care Medicine, began the project in 2009 through an R21 grant from the National Cancer Institute. The study addresses an area of growing research interest: cancer survivors’ quality of life and effects of their treatment.

“Breast cancer patients frequently report problems with memory and concentration, as well as other behavioral symptoms such as feeling tired,” Patel said. “Patients often call these symptoms ‘chemo brain,’ and they are concerned about them because they can interfere with women’s ability to successfully return to their previous, ‘normal’ lifestyle after they finish treatment.”

Several studies have shown that a subgroup of breast cancer patients have persistent troubles with these symptoms even years after treatment, but few studies have followed women to track when symptoms start and how symptoms progress after treatment.

Patel’s study has enrolled 162 postmenopausal women with breast cancer so far, comparing them to another 81 enrolled healthy women who were matched by age.

Before women started surgery or other treatment, researchers assessed their cognitive functioning, such as memory and concentration, using objective tests. They also assessed women’s level of fatigue, mood and other feelings and conditions using standardized self-report measures.

In addition, they measured levels of certain immune system-related biomarkers in the blood. Called pro-inflammatory cytokines, these substances are linked to inflammation and may be a reaction to the presence of cancer. Scientists also believe they may be linked to specific behavioral changes in people.

Researchers gathered the same information a month after women finished primary treatment, and the new ACS grant will allow them to follow up one and two years after treatment.

Patel hopes to better understand how and when symptoms arise, how long they last, their relationship to specific treatments and whether certain women are at particular risk.

“It was thought that cognitive deficits and fatigue emerged during treatment, especially if women had chemotherapy, and persisted for several years in a subgroup of women,” Patel said. “But some papers have shown a presence of symptoms in some women even before treatment.

“It may be that cytokines released due to the cancer, rather than the treatment, are causing some of these problems. We do see that many women seem to return to normal about a year after treatment.”

At the same time, she also expects to find a subgroup with persistent problems. “Among other factors, we believe women with co-morbid health conditions, such as diabetes, may be especially vulnerable for persistent difficulties,” she said.

The study should shed more light on the difference between the fatigue and declines in thinking common after menopause and declines linked to breast cancer and its treatment.

If the research shows that symptoms are related to higher-than-normal levels of cytokines, scientists may pursue ways to ease disabling symptoms by reducing cytokine levels and reducing systematic inflammation using approaches that range from medications to mind-body behavioral interventions.