Radiation-related heart disease (RHD) is an important treatment side effect for one-third of patients with cancers of the chest. There is currently no quantitative non-invasive method for detecting or monitoring RHD, and less is known about how it can be avoided. Using heart and blood samples stored in the Bergom Lab from previous heart irradiation experiments in rats, I will test for a novel cardiac biomarker, ANP, and its relationship to RHD. I will learn from the interdisciplinary radiotherapy treatment planning team of clinicians and physicists about how modern radiotherapy technology can be used to reduce the risk of RHD in patients receiving treatment for chest cancers.