Abstract 13415: Coronary Calcium Score on Standard of Care Oncologic CT Scans for the Prediction of Adverse Cardiovascular Events in Patients With Non-Small Cell Lung Cancer Treated With Concurrent Chemoradiotherapy

Introduction: Chemoradiotherapy (CRT) has been associated with increased incidence of cardiovascular (CV) adverse events (CAE) including coronary events. Coronary calcium scoring (CAC) has shown to predict coronary events beyond the traditional CV risk factors. This study examines whether CAC, measured on standard, non-gated, non-contrast chest CT (NCCT) imaging, predicts the development of CAE in patients with non-small cell lung cancer (NSCLC) treated with CRT. Methods: Patients with NSCLC who were treated with CRT at MD Anderson Cancer Center from 7/2009 until 4/2014 and who had at least one NCCT scan within 6 months from their first CRT were identified. CAC scoring was performed on NCCT scans by an expert cardiologist and a cardiac radiologist following the 2016 SCCT/STR guidelines (software: Syngo.Via, Siemens Healthcare). CAE were graded based on the most recent Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. CAE were also grouped into i. coronary/vascular events ii. arrhythmias iii. heart failure or iv. pericardial disease. All CAE were adjudicated by a board-certified cardiologist. Results: Out of a total of 193 patients, 45% were female and 91% were white. Median age was 65 years (IQR: 58-72) and median BMI was 27 kg/m 2 (24-32). Of 193 patients, 142 (74%) had CAC > 0 Agatston units (AU), 93 (48%) had CAC > 100 AU and 36 (49%) CAC > 300 AU. Twenty-nine patients (15%) developed a grade > 2 CAE during a median follow up of 26.2 months (12.7-53.5). Of those, 11 (38%) were coronary/vascular events. In the multivariate cox regression analysis, controlling for mean heart dose and pre-existing heart disease, higher CAC was independently associated with development of a grade > 2 CAE (HR: 1.04, 95% CI: 1.01-1.08, p=0.022) and with worse OS (CAC > 100 AU, HR: 1.64, 95% CI: 1.11-2.44, p=0.013). In a sub-analysis evaluating the type of the CAE, it was the coronary/vascular events that were significantly associated with higher baseline CAC (median: 676 AU vs 73 AU, p=0.035). Conclusions: CAEs are frequent in patients with NSCLC treated with CRT. CAC calculated on “standard of care” NCCT can predict the development of CAEs and specifically coronary/vascular events, as well as OS, independently from other traditional risk factors and radiation mean heart dose.