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Gliomas derived from ependymocytes that tend to present as malignant intracranial tumors in children and as benign intraspinal neoplasms in adults. They may arise from any level of the ventricular system or central canal of the spinal cord. Intracranial ependymomas most frequently originate in the fourth ventricle and histologically are densely cellular tumors which may contain ependymal tubules and perivascular pseudorosettes. Spinal ependymomas are usually benign papillary or myxopapillary tumors. (From DeVita et al., Principles and Practice of Oncology, 5th ed, p2018; Escourolle et al., Manual of Basic Neuropathology, 2nd ed, pp28-9)