RT Journal Article SR Electronic T1 Neuroimaging-Based Classification Algorithm for Predicting 1p/19q-Codeletion Status in IDH-Mutant Lower Grade Gliomas JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology SP 426 OP 432 DO 10.3174/ajnr.A5957 VO 40 IS 3 A1 Batchala, P.P. A1 Muttikkal, T.J.E. A1 Donahue, J.H. A1 Patrie, J.T. A1 Schiff, D. A1 Fadul, C.E. A1 Mrachek, E.K. A1 Lopes, M.-B. A1 Jain, R. A1 Patel, S.H. YR 2019 UL http://www.ajnr.org/content/40/3/426.abstract AB BACKGROUND AND PURPOSE: Isocitrate dehydrogenase (IDH)-mutant lower grade gliomas are classified as oligodendrogliomas or diffuse astrocytomas based on 1p/19q-codeletion status. We aimed to test and validate neuroradiologists' performances in predicting the codeletion status of IDH-mutant lower grade gliomas based on simple neuroimaging metrics.MATERIALS AND METHODS: One hundred two IDH-mutant lower grade gliomas with preoperative MR imaging and known 1p/19q status from The Cancer Genome Atlas composed a training dataset. Two neuroradiologists in consensus analyzed the training dataset for various imaging features: tumor texture, margins, cortical infiltration, T2-FLAIR mismatch, tumor cyst, T2* susceptibility, hydrocephalus, midline shift, maximum dimension, primary lobe, necrosis, enhancement, edema, and gliomatosis. Statistical analysis of the training data produced a multivariate classification model for codeletion prediction based on a subset of MR imaging features and patient age. To validate the classification model, 2 different independent neuroradiologists analyzed a separate cohort of 106 institutional IDH-mutant lower grade gliomas.RESULTS: Training dataset analysis produced a 2-step classification algorithm with 86.3% codeletion prediction accuracy, based on the following: 1) the presence of the T2-FLAIR mismatch sign, which was 100% predictive of noncodeleted lower grade gliomas, (n = 21); and 2) a logistic regression model based on texture, patient age, T2* susceptibility, primary lobe, and hydrocephalus. Independent validation of the classification algorithm rendered codeletion prediction accuracies of 81.1% and 79.2% in 2 independent readers. The metrics used in the algorithm were associated with moderate-substantial interreader agreement (κ = 0.56–0.79).CONCLUSIONS: We have validated a classification algorithm based on simple, reproducible neuroimaging metrics and patient age that demonstrates a moderate prediction accuracy of 1p/19q-codeletion status among IDH-mutant lower grade gliomas.IDHisocitrate dehydrogenaseIDHmut-Codel1p/19q-codeleted IDH-mutant LGGs, oligodendrogliomasIDHmut-Noncodelnoncodeleted IDH-mutant LGGs, astrocytomasLGGlower grade gliomaMLRmultivariate logistic regressionPPVpositive predictive valueTCGAThe Cancer Genome AtlasTCIAThe Cancer Imaging ArchiveWHOWorld Health Organization