The CAROLE (CArdiac Related Oncologic Late Effects) Study

Background: Within the United States, there are an estimated 3.1 million women alive who have been diagnosed with invasive breast cancer, and approximately 56% of them have received radiation. Worldwide, there are 1.4 million diagnosed annually and, in 2012, it was the most commonly diagnosed cancer in women. As patients continue to live longer, cardiac dose-related toxicity has become an issue which impacts millions globally. Guidelines are sorely needed for this large at-risk population of women.

Purpose: Radiation therapy to the chest has known cardiac late effects including coronary artery disease, fibrosis, and valvular dysfunction. Unfortunately, there is no clear evidence on which radiation doses to cardiac structures cause these late toxicities. As a result, these effects are often under-recognized until after patients have become symptomatic. More than half of breast cancer patients are treated with radiation, and many receive incidental cardiac irradiation. Many of these women also receive systemic therapy which may pose additional cardiac risks. The investigators data will help to establish baseline rates of pre-clinical and clinical disease, which can be used to inform preventative guidelines that are critically needed in this at-risk population. Additionally, the investigators data will provide a better definition of the radiation dose-relationship associated with cardiac toxicity so that it will be possible to predict more accurately who is at elevated risk for iatrogenic cardiac disease.

Research Plan: This study will identify and evaluate 200 breast cancer patients treated at the investigators institution (>6 years prior) who are at risk for treatment-related cardiac toxicity. All patients enrolled in the study will receive echocardiograms (echo), electrocardiograms (EKGs), and coronary calcium (CAC) CT scans in order to comprehensively evaluate for pre-clinical and clinical cardiac disease. Patients identified as having cardiac disease during testing will be offered referral to a cardiologist. Patients who received non-radiation treatments (chemotherapy, hormonal therapy, and/or surgery) will be compared to radiated patients to establish baseline rates of preclinical and clinical disease. Patients who received cardiotoxic systemic therapy (doxorubicin, trastuzumab, etc.) will also be evaluated in subgroup analysis. Among radiation patients, this study proposes a novel method of risk assessment, which is, to utilize a patient's stored treatment plan (from 2004-2011) and fuse it with patients current cardiac imaging to delineate an accurate dose relationship associated with clinical and pre-clinical disease. This is further described in the specific aims below:

Specific Aim 1: Identify baseline levels of clinical and pre-clinical disease in breast cancer patients.

Aim 1.1: Delineate the group of patients diagnosed and treated for breast cancer between 2004-2011, enroll health system patients with recent follow up (within 3 years).