DIFFERENTIAL AND DIAGNOSTIC CRITERIA OF THE RECURRENCE OF GLIOMAS IN THE POST-OPERATIONAL PERIOD USING OF DYNAMIC CONTRAST-ENHANCED MRA AND PERFUSION MRI

Abstract

Objective: to elaborate differential diagnostic criteria for recurrent gliomas after combination treatment, by using dynamic contrast-enhanced magnetic resonance angiography (DCE-MRA) and T2*-weighted perfusion magnetic resonance imaging (MRI). Material and methods. The retrospective study enrolled 16 men and 7 women (mean age 34.6±15.4 years) who had undergone multiparametric magnetic resonance imaging of the brain to prevent cancer recurrence after combination treatment. The study used the following protocols: 1) static contrast-enhanced MRI, including T2- and T1-weighted MRI, and post-contrastenhanced T1-weighted images at 5–8 minutes after DCE-MPA); 2) DCE-MPA at a dose of 0.2 mmol/kg; 3) in the presence of precontrast-enhanced T2*-weighted perfusion MRI at a dose of 0.1 mmol/kg. A morphological diagnosis was done in all cases. Tumor hemodynamics was evaluated by DCE-MRA using contrast ratios (CR or CBR) in each scanning phase, as well as contrastenhancement ratios (ER or CER) and a venous-arterial ratio in the first venous phase (VAR1). Relative Cerebral Blood Volumes (rCBV) were estimated on the contrast-enhanced T1-weighted perfusion maps. Statistical processing of the results was performed using ROC analysis. Results. According to T2*-weighted perfusion MRI and the results of a follow-up using the RECIST criteria, the investigators formed two comparison groups: 1) progressions (n = 7 (30.4%)) with increased rCBV (>1.75) and 2) stabilization (n = 16 (69.6%)) with reduced rCBV ( 1.59), stabilization was found with a decrease (VAR1<1.59), as demonstrated by DCEMRA with 64% sensitivity and 94% specificity. Conclusion. The developed classification of types of hemodynamics at DCE-MRA allows the differential diagnosis of recurrence from stabilization.