Ependymal Tumors

The 2021 WHO Brain Tumor classification update grouped ependymal tumors into 3 anatomic locations-supratentorial, posterior fossa, and spinal. Supratentorial ependymomas now include ZFTA-fusion tumors which are often cystic, hemorrhagic, and show marked edema and YAP1-fusion tumors which demonstrate garlanded peripheral solid enhancement and diffusion-restriction. Posterior fossa ependymomas are now grouped by methylation profile into category A-typical posterior fossa ependymoma and category B which present in older children with smaller lesions with a better prognosis. Spinal ependymoma is relatively unchanged by molecular characterization apart from the new MYCN-altered tumor which has poor prognosis and is often advanced/disseminated at presentation.