EXercise to prevent AnthraCycline-based Cardio-Toxicity (EXACT 2.0) in individuals with breast cancer

Although great progress has been made in treating breast cancer, long-term health may be impaired by cancer therapy. For example, some chemotherapy drugs (e.g., anthracyclines) are known to cause declines in heart health. While the impact can vary, some will experience substantial heart damage that may lead to heart failure and death. As these treatments are highly effective, there is a need to find ways to reduce the damaging effects while not interfering with its anticancer potential. As it is well-known that regular exercise can improve heart health, the purpose of this study is to explore the role of exercise as a heart protective therapy for breast cancer patients receiving heart damaging chemotherapy. Anthracyclines (AC) are a highly effective anticancer drug therapy that is unfortunately known to cause permanent declines in heart health and function. Damage to the heart can ultimately lead to heart failure and death. As a result, cardiovascular disease risk has become a significant complication of AC-based treatment for breast cancer (BC). Thus, there is an immediate need to find a therapy that can protect the heart from AC without decreasing its anticancer potential. Evidence from animal studies have shown that aerobic exercise (AE) performed before or during therapy can protect the heart against the damaging effects of AC therapy. AE has been shown to prevent structural changes associated with AC-based therapy and maintain/improve the pumping ability of the heart, however these benefits have not been demonstrated in women with BC. Therefore, studies need to be conducted in BC patients receiving AC therapy to determine if AE protects the heart. This study will explore the impact of an aerobic exercise (AE) program on heart health in breast cancer patients receiving a form of chemotherapy known to cause irreparable damage to the heart. To do this we will compare a group of patients who receive an AE program to a group of patients who will receive standard care (i.e., no AE). Patients will be randomly assigned to either the AE or standard care group. Those assigned to the AE will receive a 12-week, 2x/week home-based AE program. Patients assigned to the standard care group will be given the opportunity to participate in the full AE program at the end of the study. New types of heart scans will be used to see how the heart is working. Small proteins that are found in the blood (e.g. biomarkers) that indicate early heart damage also will be examined. Measures of heart health along with quality of life will be examined pre- and post-intervention as well as 6 months after the intervention has been completed. While the use of exercise to improve heart health and decrease the risk of heart disease has been well-documented, much less is known of its potential benefits for breast cancer patients receiving the heart toxic chemotherapy anthracycline. This research will help bridge the gap between the heart protective effects of pre- and on-treatment exercise proposed by animal studies. The advancements this study will offer to both the medical and research community will be of the utmost importance in both improving the long-term health of breast cancer survivors as well as further improving the understanding of the processes by which heart protective benefits may be attained. Given the significant impact anthracycline-based chemotherapy treatment has on improving cancer prognosis, and the potential protective effects of exercise training, this study will be instrumental in fostering improved supportive cancer care and optimizing survivorship. ICR-CIHR 2018/2019 $100,000