Optimized monitoring for immune checkpoint inhibitor induced myocarditis using high-sensitivity troponin-T

Background: Immune checkpoint inhibitor (ICI)-induced Myocarditis (irMyocarditis) is a rare adverse event with a high mortality rate of 40-50 % and which is mostly not diagnosed until clinical symptoms emerge.

Objectives: This study aims to screen patients for irMyocarditis using high-sensitivity cardiac troponin-T (hs-TnT) before and regularly during therapy with ICI.

Methods: A cohort of 280 cancer patients were prospectively screened for levels of hs-TnT at baseline and prior to every ICI infusion. In case of elevation of hs-TnT, patients were referred for further work-up.

Results: In total, 196 patients exhibited a baseline hs-TnT ≤ 14 ng/l (99th percentile concentration for general population; group A) and 84 patients a hs-TnT > 14 ng/l at baseline (group B). An increase of hs-TnT during ICI-treatment was observed in 56 out of 196 (27.6 %) and 56 out of 84 patients (66.7 %) in group A and B. Cardiovascular assessment was performed in 11.2 % and 27.4 % of patients, respectively, and 4.1 % and 9.5 % of patients were diagnosed with irMyocarditis and treated with corticosteroids. No fatalities occurred in any of the 16 irMyocarditis patients. Defining a threshold with the highest sensitivity and maximum specificity in receiver-operating characteristics curves, identified a limit of 22 ng/l (group A) and 60 ng/l (group B) hs-TnT, associated with a sensitivity of 100 % in both and a specificity of 91.0 % and 89.6 %, respectively, to detect irMyocarditis.

Conclusion: Screening of hs-TnT can identify irMyocarditis early and lead to reduction of MACE and mortality risk through interruption of ICI-treatment and prompt therapy with corticosteroids.