10217- NI-17 COMPARISON OF DYNAMIC SUSCEPTIBILITY CONTRAST PERFUSION MRI WITH 11C-METHIONINE PET IN ADULT NON-CONTRAST ENHANCED GLIOMAS

Abstract OBJECTIVE This study examined the correlation between cerebral blood volume (CBV) and MET PET. SUBJECTS AND METHODS 108 non-contrast-enhanced gliomas (41.8±12.3 years old, 58 males) examined between April 2012 and December 2022 were included. The pathological diagnosis was Glioblastoma, IDH-wildtype (G): 21 cases, Astrocytoma, IDH-mutant (A): 52, Oligodendroglioma, IDH-mutant and 1p/19q codeleted (O): 35. T2 region (the high signal region on T2WI) on MRI and high-MET region (tumor maximum SUV/normal frontal cortex SUV (T/N) ratio > 1.3) on MET PET were defined. The rCBV (regional mean CBV/normal white matter mean CBV) was calculated using dynamic-susceptibility-contrast perfusion MRI to compare each region. RESULT The rCBV (3.22±0.95) in the T2 region in 67 patients with MET accumulation was significantly higher than those (2.47±0.64) in 41 patients without MET accumulation (p<0.0001). The cutoff rCBV value obtained from the ROC curve for MET accumulation was 2.79, with a sensitivity of 61.2%, specificity of 75.6%, and AUC of 0.73. The rCBV in the T2 region was (G: 3.60±1.0 A: 2.53±0.69 O: 3.14±0.89) significantly higher in group G (p<0.0001). In the 69 patients with MET accumulation (G: 16, A: 21, O: 30), the rCBV was 3.23±0.96 in the T2 region and 3.48±1.13 in the high-MET region, significantly higher in the latter (p<0.0016). The rCBV was significantly higher in the group G both in the T2 region (G: 3.82±0.97 A: 2.77±0.68 O: 3.22±0.93, p=0.0026) and in the high-MET region (G: 4.12±1.18 A: 3.29±1.0 O: 3.27±1.1, p=0.031). The difference was most in the group A (p=0.016). The rCBV significantly correlated with T/N ratio in both the T2 region (r=0.41, p=0.0005) and the high-MET region (r=0.49, p<0.0001), mainly observed in groups A and O. DISCUSSION The rCBV and MET accumulation correlated in non-contrast-enhanced gliomas. The CBV may be an alternative to MET PET in imaging gliomas.