Abstract 9343: Predictive Value of Baseline Serum High-Sensitivity Troponin I and NT-proBNP for Cardiac Immunotoxicity Risk During Immune Checkpoint Inhibitor Therapy

Abstract

Introduction: Immune checkpoint inhibitors (ICI) have revolutionized cancer treatment, but rarely and unpredictably cause fulminant myocarditis. It is unknown if circulating cardiac biomarkers can predict immunotoxicity in a real-world patient population. Aim: To evaluate the predictive value of baseline levels of high-sensitivity troponin-I (hs-TnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) for myocardial injury (hs-TnI>50ng/L) or potential heart failure (NT-proBNP>300pg/mL) risk during ICI therapy. Methods: An institutional multidisciplinary working group developed a monitoring protocol for immune-related adverse events due to ICI. Data recorded during clinical treatment plans over 12 months starting 5/1/2021 were analyzed. Results: 621 patients received ICI therapy, and 6 developed myocarditis requiring hospitalization. Of 317 patients initiated on ICI after the start of this protocol, baseline and at least one follow-up hs-TnI and NT-proBNP values were measured in 183 and 126 patients, respectively. In 110 patients hs-TnI was undetectable (<5ng/L) at baseline. In 66% of these patients hs-TnI remained undetectable on follow-up. Of 88 patients with baseline NT-proBNP below the diagnosis limit for heart failure (<300 pg/mL), 75% had values below this limit on follow-up. The baseline value of the biomarkers was used as a predictor of increase in biomarkers during follow-up. Area under receiver operator curve for predicting an increase from baseline during ICI treatment was 0.67 for hs-TnI, 0.87 for NT-proBNP, and 0.86 combined (Figure). Conclusions: This single-center, prospectively protocolled, retrospectively-analyzed study indicates that hs-TnI and NT-proBNP values obtained at baseline and at least at one immunotherapy cycle can be used to categorize patients at risk or not for potential immunotoxicity during ICI treatment, thus may offer a helpful strategy in the monitoring and prevention of fulminant myocarditis.