Initial experience of the implementation of a cardio-oncology program for breast cancer patients receiving modern radiotherapy in a tertiary institution

Background: The modern era of multimodality cancer treatment strategies has contributed to a much longer survival time of breast cancer patients. Accordingly, cardiovascular toxicity related to anticancer therapy including radiation-induced heart disease has become an issue of concern. To address this issue, it is important to develop cardio-oncology programs to provide cardiovascular assessment, surveillance and management for patients receiving cancer therapy with potential heart impairment. Methods: A multidisciplinary cardio-oncology combined care team and clinical protocol were established. Cardiac assessments of patients at risk before radiation, and surveillance and management of cardiotoxicity after completing cancer therapy were performed. A novel radiotherapy planning technique with complete-directional-complete block in helical tomotherapy was used to reduce cardiac exposure dose and limit heart damage. We analyzed the effect in the patients receiving this modern technique and cardio-oncology care. Results: The number of breast cancer patients receiving cardio-oncology care increased annually, from 64 (71.9%) in 2013 to 177 (81%) in 2019. A series of cardiac assessments were performed, including cardiac biomarkers, electrocardiogram, echocardiogram, and/or myocardial perfusion imaging to evaluate the patient's cardiac risk or development of subsequent cardiotoxicity after cancer therapy. Among the 303 patients who were treated with the modern radiotherapy technique, 15 (5%) were diagnosed with cardiovascular disease by the combined care program. Conclusions: For the breast cancer patients receiving multimodality cancer treatment with modern radiotherapy in this study, the multidisciplinary cardio-oncology program of screening, prevention, management and follow-up protocols reduced cancer therapy-related cardiovascular toxicity, and improved the clinical outcomes and quality of life for long-term survivors.