MR textural analysis on T2 FLAIR images for the prediction of true oligodendroglioma by the 2016 WHO genetic classification

BackgroundThe genetic status of 1p/19q is important for differentiating oligodendroglioma, isocitrate-dehydrogenase (IDH)-mutant, and 1p/19q-codeleted from diffuse astrocytoma, IDH-mutant according to the 2016 World Health Organization (WHO) criteria. PurposeTo assess the value of magnetic resonance textural analysis (MRTA) on T-2 fluid-attenuated inversion recovery (FLAIR) images for making a genetically integrated diagnosis of true oligodendroglioma by WHO guidelines. Study TypeRetrospective case control. SubjectsIn all, there were 54 patients with a histopathological diagnosis of diffuse glioma (grade II). All were tested for IDH and 1p/19q. Field Strength/Sequence3.0T, including T-2 FLAIR sequence, axial T-1-weighted, and T-2-weighted sequence. AssessmentMRTA on a representative tumor region of interest (ROI) was made on preoperative T-2 FLAIR images around the area that had the largest diameter of solid tumor using Omni Kinetics software. Statistical TestsDifferences between IDH-mutant and 1p/19q-codeleted and IDH-mutant and 1p/19q-intact gliomas were analyzed by the Mann-Whitney rank sum test. Receiver operating characteristic curves (ROC) were created to assess MRTA diagnostic performance. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated with a cutoff value according to the Youden Index. ResultsComparisons demonstrated significant differences in kurtosis (P=0.007), energy (0.008), entropy (0.008), mean deviation (MD) (<0.001), and high gray-level run emphasis (HGLRE) (0.002), cluster shade (0.025), and sum average (0.002). First-order features comprising entropy (area under the curve [AUC]=0.718, sensitivity=97.1%) and energy (0.719, 94.1%) had the highest sensitivity but lower specificity (both 45%). Second-order features such as HGLRE (AUC=0.750, sensitivity=73.5%, specificity=80.0%) and sum average (0.751, 70.6%, 80.0%) had relatively higher specificity, and all had AUC >0.7. MD had the highest diagnostic performance, with AUC=0.878, sensitivity=94.1%, specificity=75.0%, PPV=86.5%, and NPV=88.2%. Data ConclusionMRTA on T-2 FLAIR images may be helpful in identifying oligodendroglioma, IDH-mutant, and 1p/19q-codeleted. Level of Evidence: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017.