Exercise, Cancer and Cognition: The ECCO-Study

Background: Epidemiological research indicates that increased levels of physical activity are associated with decreased breast cancer risk and mortality. Thereby, exercise programs can substantially increase patients' quality of life during and after treatment. Up to 80% of breast cancer patients demonstrate a decrease in their cognitive capacity, summarized as the symptom-complex "Cancer Related Cognitive Impairment (CRCI)". Most frequently reported impairments are mild to moderate deficits in processing speed, attention, memory and executive functions. In about 35% of affected patients, cognitive symptoms persist for months, or even years, after completion of medical treatment, impairing daily functioning, limiting ability to return to work and decreasing overall quality of life. Recent studies indicate a key role of inflammatory pathways in the CRCI genesis. Attention to physical activity therefore as a potential supportive care option is increasing. Anyhow, evidence for positive effects of exercise on CRCI is still lacking. Patients and Methods: This prospective, two-arm, 1:1 randomized, controlled trial aims to investigate the influence of high-intensity training interventions accompanying neo/-adjuvant chemotherapy on CRCI in 126 patients with early breast cancer on cognitive performance measured by the California Verbal Learning Test (CVLT). Secondary endpoints include subjective markers and tests for cognitive performance and inflammatory biomarkers as TNF-α, IL-6, IL-1α, IL-1ß which are suspected to be involved in the pathogenesis of CRCI. As cognitive impairments are believed to be connected to either functional and/or morphological hippocampal damage due to chemotherapy, head MRIs and hippocampal volume measurements will be performed. In addition to a heart rate controlled home-based endurance and strength training for one year, participants in the intervention group will perform a supervised high-intensity interval training (HIIT) exercise program at least once a week. This study will help to clarify whether a long-term supervised exercise intervention program affects CRCI in breast cancer patients and help to reason underlying mechanisms and the pathogenesis of the chemobrain.