The Role of Myocardial SPECT in Evaluation of Irradiation-induced Changes.

Helical tomotherapy nowadays provides the most precise data on radiotherapy (RT) dose delivered to each region of the heart in left-sided breast cancer therapy, which allows greater sparing of the heart from doses associated with increased complications. However, heart disease shows a wide spectrum of pathologies, and multiple risk factors related. The damage of the myocytes may lead to not only myocardial perfusion defects, but also in functional deterioration, or even in biomarkers. In this study, we will monitor cardiovascular (CV) risk factors, metabolism, biomarkers, myocardial perfusion defect patterns, and cardiac functional parameters, in order to delineate of RT-related effects and clinical impacts. Objective: The pilot study aims to investigate the correlation of post-tomotherapy cardiovascular effects with myocardial perfusion and cardiac functional studies. Methods: The study plans to enroll female breast cancer patients who will undergo local RT after their surgery. Patients will receive global risk scoring assessment (Framingham Risk Score, FRS), blood sampling for basic biochemistry, inflammatory biomarker, and myocardial perfusion image (MPI) at the time points of before and after RT. The results of MPI will be analyzed in qualitative visual interpretation of perfusion patterns, and functional quantitative data for cardiac functional parameters as well. The patients will be regular followed-up in CV OPD. The association between baseline and follow-up MPI, biomarker and clinical presentation will be further investigated.