P1.16-20 Trial in Progress: Cardiac Toxicity in Patients Undergoing Curative Intent Radiotherapy for Lung Cancer

Background: The cardiotoxic effects of radiotherapy (RT) in long term survivors of breast cancer or lymphoma are well documented. Post-mortem studies and animal models have shown that RT causes fibrosis of cardiac structures leading to a wide variety of cardiac pathology. RTOG 0617 has highlighted a link between survival and cardiac dose and has led to a number of studies of cardiac toxicity in lung cancer patients. It is difficult to draw conclusions on cardiac dose constraints from available studies due to their retrospective nature and heterogeneity. We present an ongoing multicentre retrospective data mining study and prospective trial of cardiac biomarkers and imaging in patients undergoing radical lung RT, the aim of which is to define cardiac dose contraints leading to cardiac sparing treatment strategies. Method(s): Retrospective Validation Image based data mining results for heart substructures will be validated using a larger cohort. We will obtain data from Public Health England on cardiac risk factors, hospital admissions and cause of death for these patients to conduct a multivariate survival analysis. Clinical Trial (NCT03645317) A prospective study will collect cardiac risk factors (Qrisk 3), detailed cardiac imaging (CT and echocardiogram), ECG and cardiac blood biomarkers to evaluate effect of the radiotherapy on the heart. [Figure presented] Result: Over 4000 patients treated with curative intent RT from 1/1/2010 to 30/12/206 have been identified. Details on 600 patients have been obtained and will be presented at WCLC 2019. Fifty-two patients (9%) had cardiac events following RT. The prospective trial is due to open in May 2019 Conclusion(s): Studies of cardiac toxicity in lung RT have so far mainly been heterogeneous and retrospective. We describe a package of work incorporating large retrospective datasets with prospective imaging and blood biomarker collection to define cardiac dose parameters. This will improve the outcomes of lung cancer patients treated with radical radiotherapy by limiting heart dose and reducing cardiac events. Keywords: cardiac toxicity, cardiac imaging, radiotherapyCopyright © 2019