%0 Journal Article %A S. Perreault %A V. Ramaswamy %A A.S. Achrol %A K. Chao %A T.T. Liu %A D. Shih %A M. Remke %A S. Schubert %A E. Bouffet %A P.G. Fisher %A S. Partap %A H. Vogel %A M.D. Taylor %A Y.J. Cho %A K.W. Yeom %T MRI Surrogates for Molecular Subgroups of Medulloblastoma %D 2014 %R 10.3174/ajnr.A3990 %J American Journal of Neuroradiology %X BACKGROUND AND PURPOSE: Recently identified molecular subgroups of medulloblastoma have shown potential for improved risk stratification. We hypothesized that distinct MR imaging features can predict these subgroups. MATERIALS AND METHODS: All patients with a diagnosis of medulloblastoma at one institution, with both pretherapy MR imaging and surgical tissue, served as the discovery cohort (n = 47). MR imaging features were assessed by 3 blinded neuroradiologists. NanoString-based assay of tumor tissues was conducted to classify the tumors into the 4 established molecular subgroups (WNT, sonic hedgehog, group 3, and group 4). A second pediatric medulloblastoma cohort (n = 52) from an independent institution was used for validation of the MR imaging features predictive of the molecular subtypes. RESULTS: Logistic regression analysis within the discovery cohort revealed tumor location (P < .001) and enhancement pattern (P = .001) to be significant predictors of medulloblastoma subgroups. Stereospecific computational analyses confirmed that group 3 and 4 tumors predominated within the midline fourth ventricle (100%, P = .007), WNT tumors were localized to the cerebellar peduncle/cerebellopontine angle cistern with a positive predictive value of 100% (95% CI, 30%–100%), and SHH tumors arose in the cerebellar hemispheres with a positive predictive value of 100% (95% CI, 59%–100%). Midline group 4 tumors presented with minimal/no enhancement with a positive predictive value of 91% (95% CI, 59%–98%). When we used the MR imaging feature–based regression model, 66% of medulloblastomas were correctly predicted in the discovery cohort, and 65%, in the validation cohort. CONCLUSIONS: Tumor location and enhancement pattern were predictive of molecular subgroups of pediatric medulloblastoma and may potentially serve as a surrogate for genomic testing. Abbreviations CP/CPAcerebellar peduncle/cerebellopontine angle cisternFSLfMRI of the Brain Software LibrarySHHsonic hedgehogWNTwingless %U https://www.ajnr.org/content/ajnr/early/2014/05/15/ajnr.A3990.full.pdf