Diffuse glioma molecular profiling with Arterial Spin Labeling and Dynamic Susceptibility Contrast perfusion MRI: a comparative study

Evaluation of molecular markers (IDH, pTERT, 1p/19q co-deletion, and MGMT) in adult diffuse gliomas is crucial for accurate diagnosis and optimal treatment planning. Dynamic Susceptibility Contrast (DSC) and Arterial Spin Labeling (ASL) perfusion MRI techniques have both shown good performance in classifying molecular markers, however, their performance has not been compared side-by-side. Pre-treatment MRI data from ninety patients diagnosed with diffuse glioma (54 men/36 female, 53.1 ± 15.5 years, grades 2-4) were retrospectively analyzed. DSC-derived normalized cerebral blood flow/volume (nCBF/nCBV) and ASL-derived nCBF in tumor and perifocal edema were analyzed in patients with available IDH–mutation (n=67), pTERT–mutation (n=39), 1p/19q co-deletion (n=33), and MGMT promoter methylation (n=31) status. Cross-validated uni- and multivariate logistic regression models assessed perfusion parameters’ performance in molecular marker detection. ASL and DSC perfusion parameters in tumor and edema distinguished IDH-wildtype (wt) and pTERT-wt tumors from mutated ones. Univariate classification performance was comparable for ASL-nCBF and DSC-nCBV in IDH (maximum AUROCC 0.82 and 0.83, respectively) and pTERT (maximum AUROCC 0.70 and 0.81, respectively) status differentiation. The multivariate approach improved IDH (DSC-nCBV AUROCC 0.89) and pTERT (ASL-nCBF AUROCC 0.8, DSC-nCBV AUROCC 0.86) classification. However, ASL and DSC parameters could not differentiate 1p/19q co-deletion or MGMT promoter methylation status. Positive correlations were found between ASL-nCBF and DSC-nCBV/-nCBF in tumor and edema. ASL is a viable gadolinium-free replacement for DSC for molecular characterization of adult diffuse gliomas.