Losartan for Reducing Radiation Therapy-induced Cardiac Fibrosis in Patients Undergoing Radiation Therapy for Non-Metastatic Breast Cancer
This early phase I trial evaluates the effectiveness of losartan for reducing radiation therapy-induced cardiac fibrosis in patients undergoing radiation therapy for left-sided breast cancer that has not spread from where it first started (primary site) to other places in the body (non-metastatic). Radiation therapy is a common and effective form of treatment for breast cancer patients, and is widely used for the treatment of many different cancers. However, patients receiving radiation therapy have an increased risk of damage to the heart, especially patients with left-sided breast cancer. Cardiac fibrosis (the thickening of the heart tissue) is one form of heart damage that may result from treatment with radiation therapy, and which can lead to heart failure. Losartan is a type of drug known as an angiotensin II receptor blocker. It blocks the action of certain chemicals that make blood vessels constrict (get narrower), and is commonly used to treat high blood pressure. Losartan may be effective in reducing cardiac fibrosis among breast cancer patients undergoing radiation therapy.