ECV improves diagnostic performance of the CMR mass score in primary cardiac tumor characterisation

Background Parametric mapping has been underexplored for differentiating benign and malignant cardiac tumors, and its incremental value beyond conventional cardiovascular magnetic resonance (CMR) mass scores remains unclear. Purpose To evaluate whether parametric mapping of cardiac tumors and myocardium improves the diagnostic performance of the CMR score for distinguishing benign from malignant cardiac tumors. Methods Patients who underwent CMR for suspected cardiac tumors from January 2018 to December 2024 was performed retrospectively. Diagnosis of benign or malignant cardiac tumors was based on pathology or comprehensive history evaluation, other imaging and long-term follow-up data. Parametric mapping values were measured on cardiac tumors and left ventricular myocardium. Univariate and multivariate logistic regression analysis were used to find independent predictors of CMR parametric mapping for benign and malignant cardiac tumors. The independent predictors of parametric mappings were included in the available CMR score and the performance was compared using the areas under the receiver operating characteristic curves (AUC), sensitivity, specificity and accuracy. Results Eventually 186 patients were included in this study (age, 44±22; 102 males, 122 females), 144 benign and 43 malignant. The ECV of the myocardium peri-tumor (ECV-peri) and remote-tumor (ECV-remote) were independent risk factors for malignant cardiac tumors (OR=1.321, p<0.001; OR=1.641, p<0.001) at the optimal cut-off values of 29.35% and 26.25%, respectively, which were turned into dichotomous variables. The AUC, sensitivity and specificity of the available CMR score, the improved CMR score, and the new CMR score were respectively 0.899, 72.7%, 78.9%, 77.4%; 0.956, 93.2%, 88.7%, 89.9 and 0.970, 91.4%, 90.9%, 91.5%. Conclusion Parametric mapping especially ECV-peri and ECV-remote can improve CMR score for the diagnosis of benign and malignant cardiac tumors and provide new imaging parameters.