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Medulloblastoma is the classic pediatric tumor that arises from the midline cerebellar vermis; it is the most common malignant posterior-fossa neoplasm in children, whereas cerebellar astrocytomas are usually hemispheric, ependymomas originate from the fourth-ventricle floor, and glioblastoma multiforme is rare in this age group [Bhaskar et al., 2017, PMID 28192784].