Low-grade and anaplastic oligodendrogliomas: Differences in tumour microvascular permeability evaluated with dynamic contrast-enhanced magnetic resonance imaging

This study was designed to quantitatively assess the microvascular permeability of oligodendroglioma using the volume transfer constant (K-tran) and the volume of the extravascular extracellular space per unit volume of tissue (V-e) with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). We aimed to evaluate the effectiveness of K-trans and V-e in distinguishing between low-grade and anaplastic oligodendroglioma. The maximal values of K-trans and V-e for 65 patients with oligodendroglioma (27 grade II, 38 grade III) were obtained. Differences in K-trans and V-e between the two groups were analysed using the Mann-Whitney rank-sum test. Receiver operating characteristic (ROC) curve analyses were performed to determine the cut-off values for the K-trans and V-e that could differentiate between low-grade and anaplastic oligodendrogliomas. Values for K-trans and V-e in low-grade oligodendrogliomas were significantly lower than those in anaplastic oligodendrogliomas (p < 0.001 and p < 0.001, respectively). ROC curve analysis showed that cut-off values of the K-trans (0.037 min(-1)) and V-e (0.079) could be used to distinguish between low-grade and anaplastic oligodendrogliomas in a statistically significant manner. Our results suggest that DCE-MRI can distinguish the differences in microvascular permeability between low-grade and anaplastic oligodendrogliomas. (C) 2012 Elsevier Ltd. All rights reserved.