1092 - Coronary Artery Calcifications and Major Adverse Cardiac Events after Radiation Therapy for Locally-Advanced Non-Small Cell Lung Cancer
Presenter(s)
C. R. Kelsey1, Y. Chung2, E. Evani1, D. Neish3, G. J. Kim4, P. Karukonda4, T. C. Mullikin5, Y. Cui1, D. Niedzwiecki6, J. Christensen5, D. LaBella3, J. Crawford5, and H. I. Yoon7; 1Department of Radiation Oncology, Duke University Medical Center, Durham, NC, 2Department of Nuclear Engineering, Hanyang University, Seoul, Korea, Republic of (South), 3Duke University, Durham, NC, 4Duke University Medical Center, Department of Radiation Oncology, Durham, NC, 5Duke University Medical Center, Durham, NC, 6Department of Biostatistics and Bioinformatics, Duke University Medical Center, Durham, NC, 7Department of Radiation Oncology, Yonsei Cancer Center, Heavy Ion Therapy Research Institute, Yonsei University College of Medicine, Seoul, Korea, Republic of (South)
Purpose/Objective(s): Patients with locally advanced non–small cell lung cancer (NSCLC) treated with concurrent chemoradiotherapy (CRT) are at elevated risk for cardiac morbidity due to baseline cardiovascular risk factors and radiation dose to cardiac substructures. We hypothesized that underlying atherosclerotic disease, reflected by coronary artery calcification (CAC), further increases susceptibility to post-CRT cardiac complications. We evaluated the association between CAC and major adverse cardiac events (MACE), defined as unstable angina, coronary revascularization, myocardial infarction, congestive heart failure, or cardiac death.
Materials/Methods: Patients with stage II–III NSCLC completing CRT from 2007–2021 were reviewed. Those with a non-contrast diagnostic chest CT within 6 months of diagnosis were included. Baseline cardiac risk factors (hypertension [HTN], familial hypercholesterolemia [FH], diabetes mellitus [DM], tobacco use), pre-existing cardiac disease, and post-treatment cardiac events were collected. The heart and 15 cardiac substructures were contoured on planning CT scans. CAC scores were calculated using an automated algorithm (Aview CAC; Coreline Soft). Cumulative incidence of MACE was estimated accounting for competing non-cardiac mortality. Univariable and multivariable Fine and Gray competing risks regression with backward selection identified predictors.
Results: Among 320 treated patients, 275 had evaluable CAC imaging; 174 had thin-section CT (1–1.5 mm) and 101 standard-section CT (3–5 mm). Median age was 66 years (range, 59–73); 54% were male. Baseline HTN, FH, DM, and tobacco use < 5 years from diagnosis were present in 56%, 41%, 24%, and 51%, respectively. Pre-existing cardiac disease was present in 82 patients (30%), most commonly coronary artery disease (n=51, 19%). RT technique was 3D (48%) or IMRT (52%); median dose was 60 Gy (range, 58–74 Gy). Chemotherapy included carboplatin/paclitaxel (44%), cisplatin/etoposide (28%), and other regimens (28%); 25% received adjuvant immunotherapy. CAC scores were 0, 1–99, 100–299, and =300 in 19%, 31%, 15%, and 35%, respectively. At a median follow-up of 45 months, 27 patients developed MACE. The 5-year cumulative incidence was 9%. On univariable analysis, CAC =300, pulmonary vein D0.03cc dose, and 3D RT technique predicted MACE. Multivariable analysis retained pulmonary vein D0.03cc dose (HR 1.04, 95% CI 1.02–1.06, p=0.001), 3D RT (HR 5.75, 95% CI 2.63–12.59, p<0.001) and adjuvant immunotherapy (HR 3.56, 95% CI 1.68–7.51, p<0.001); CAC =300 (HR 1.98, 95% CI 0.94–4.19, p=0.073). In an analysis restricted to patients with thin-section CT, CAC =300 was significant (HR 2.60, 95% CI 1.08–6.23, p=0.032).
Conclusion: CAC scores derived from diagnostic chest CT, ideally thin-cut studies, provides meaningful risk stratification for post-treatment MACE following CRT. CAC scoring may inform referral to high-risk cardio-oncology clinics and guide targeted cardiovascular risk reduction strategies