2035P - Routine biomarker monitoring does not replace comprehensive clinical assessment in the detection of immunotherapy induced myocarditis

Background

Multiple international guidelines suggest that pre-treatment cardiac markers should be taken prior to each cycle of treatment to support the early diagnosis and treatment of immune checkpoint inhibitor (ICI) induced myocarditis (1). As a large regional tertiary cancer centre with an established cardio-oncology service early adoption of baseline and subsequent cardiac surveillance has been implemented and its utility evaluated.

Methods

A retrospective analysis of patients whom had undergone baseline cardiac assessment prior to receiving ICI treatment at the Clatterbridge Cancer Centre between October 2022 and March 2023 was performed. Within the regional protocol all patients with abnormal cardiac markers (Pro-B Naturetic Peptide (Pro-BNP) >400 ng/L and or a high sensitivity troponin T (TropT) >14 ng/L) were subsequently monitored with pre-cycle cardiac biochemical monitoring for the first 3 cycles of ICI treatment.

Results

400 patients who commenced ICI treatment underwent baseline cardiac screening. Of these 169 patients (42.2%) had abnormal biomarkers: 36% (n=61) elevated TropT; 32% (n=54) elevated pro-BNP and 32% (n=54) had elevations in both. Within this cohort 3.3% (n=13) patients were diagnosed with ICI-induced myocarditis; 12 confirmed on cardiac MRI (cMRI) and 1 clinically diagnosed due to clinical instability. Of these 69% (n=9) patients had abnormal baselines and thus had pre-cycle monitoring; 4 did not. Of these 9; 8 were detected through symptoms alone; 1 patient was found to have elevated biomarkers but had already been clinically assessed prior to treatment and had been admitted prior to the biomarker results being reviewed.

Conclusions

Baseline cardiac assessment is useful, as the majority of patients that go on to develop ICI myocarditis have abnormal baseline values. However, the clinical utility of pre-cycle screening has not demonstrated enhanced or earlier detection of myocarditis compared to clinical assessment and represents an area of potential cost saving. Patients are either presenting mid-cycle or are identified via symptomatic review therefore investment is better placed in education and training to optimize clinical recognition and timely management.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

R. Dobson: Financial Interests, Personal, Invited Speaker: BMS, Roche. N. Garbutt: Financial Interests, Personal, Invited Speaker: BMS. T. Guinan: Financial Interests, Personal, Invited Speaker: BMS, MSD, Roche, Sanofi. A.C. Olsson-Brown: Financial Interests, Personal, Invited Speaker: BMS, MSD, Roche, Novartis, AZ, Eisai, B-I. All other authors have declared no conflicts of interest.