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.