Characterization of Immune Checkpoint Inhibitor-Related Cardiotoxicity in Lung Cancer Patients From a Rural Setting

BACKGROUND: Immune checkpoint inhibitor (ICI)-related cardiotoxicity (iRC) is uncommon but can be fatal. There have been few reports of iRC from a rural cancer population and few data for iRC and inflammatory biomarkers. OBJECTIVES: The purpose of this study was to characterize major adverse cardiac events (MACE) in ICI-treated lung cancer patients based in a rural setting and to assess the utility of C-reactive protein (CRP) and neutrophil-lymphocyte ratio (NLR) in the diagnosis of iRC. METHODS: Patients with lung cancer treated with ICIs at Vidant Medical Center/East Carolina University (VMC/ECU) between 2015 and 2018 were retrospectively identified. MACE included myocarditis, non-ST-segment elevated myocardial infarction (NSTEMI), supraventricular tachycardia (SVT), and pericardial disorders. Medical history, laboratory values, pre-ICI electrocardiography (ECG), and echocardiography results were compared in patients with and without MACE. RESULTS: Among 196 ICI-treated patients, 23 patients (11%) developed MACE at a median of 46 days from the first ICI infusion (interquartile range [IQR]: 17 to 83 days). Patients who developed MACE experienced myocarditis (n = 9), NSTEMI (n = 3), SVT (n = 7), and pericardial disorders (n = 4). Ejection fraction was not significantly different at the time of MACE compared to that at baseline (p = 0.495). Compared to baseline values, NLR (10.9 ± 8.3 vs. 20.7 ± 4.2, respectively; p = 0.032) and CRP (42.1 ± 10.1 mg/l vs. 109.9 ± 15.6 mg/l, respectively; p = 0.010) were significantly elevated at the time of MACE. CONCLUSIONS: NLR and CRP were significantly elevated at the time of MACE compared to baseline values in ICI-treated patients. Larger datasets are needed to validate these findings and identify predictors of MACE that can be used in the diagnosis and management of ICI-related iRC.