Cardiovascular disease (CVD) is the second most common cause of death in breast cancer patients. Certain adjuvant treatments (eg. anthracyclins, radiotherapy) increase the risk of CVD, in particular in patients with pre-existing cardiovascular risk factors. Early identification of patients with cardiovascular risk factors enables targeted cardiopreventive interventions, and switching to less cardiotoxic treatments. To goal of this project is to develop a tool for identification of patients at increased risk of CVD using radiotheraphy treatment planning CT. The project is part of the a larger projecttitled Automated quantification of coronary artery calcifications on radiotherapy treatment planning CT scans for accurate cardiovascular risk prediction in women with breast cancer funded by Dutch Cancer Foundation and performed in collaboration between Image Sciences Institute and Imaging Division at the UMC Utrecht.