151P Myocardial strain evaluation with cardiovascular MRI in patients with locally-advanced NSCLC treated with chemotherapy and radiation therapy

The standard of care for patients with unresectable stage III non-small cell lung cancer (NSCLC) is platinum-based chemotherapy concurrent with thoracic radiotherapy (CRT), followed by durvalumab consolidation if tumor PDL1 expression is ≥1%. CRT is associated with increased risks of developing cardiac dysfunction. Myocardial strain is a measure of myocardial deformation, which is a more sensitive imaging biomarker of myocardial disease than the left ventricular ejection fraction (LVEF). Cardiovascular MRI (CMR) myocardial strain is emerging as an early marker of cardiotoxicity of anticancer treatments. We conducted a retrospective analysis of patients with stage III NSCLC treated with CRT at our institution between April 2017 and March 2023. We used a CMR to assess the myocardial strain in all surviving patients with no known cardiac comorbidity. We evaluated the percentage of patients with abnormal myocardial strain, which was defined as having less than 75% of normal myocardium. Additionally, we examined the patients' demographics and clinical characteristics of the cohort. Of 96 patients with stage III NSCLC treated with CRT, 51 were alive in June 2023. 12 patients were excluded for having known cardiac comorbidity, and 12 declined to participate in the study. 27 patients underwent CMR between May and August 2023 and were included in the analysis. 18 patients (66.7%) had abnormal myocardial strain (Cohort A), versus 9 patients with % normal myocardium >75% (Cohort B). Compared with Cohort B, pts with altered myocardial strain (Cohort A) were more frequently men (22.2 vs 72.2%), and current/former smokers (77.8 vs 100%), p<0.05. In our cohort of 27 patients with stage III NSCLC treated with CRT who underwent CMR, the percentage of patients with abnormal myocardial strain was high (66.7%). Prospective studies with CMR myocardial strain performed pre- and post-CRT are warranted to explore the sensitivity and specificity of this technology to assess the cardiotoxicity of anticancer treatments, as well as its clinical utility to prevent cardiac dysfunction.