Prognostic relevance of localization and grading in intracranial ependymomas of childhood.

Intracranial ependymomas represent one of the most frequent brain tumors in childhood. Their preferred midline localization and their often controversially discussed classification prompted the present study of 67 intracranial ependymomas in children less than 15 years of age who were operated on from 1951 to 1990. Clinical data and follow-up of all children were retrospectively analyzed by calculation and statistical comparison of progression-free survival (PFS). According to the WHO classification as revised in 1993, 1 grade I subependymoma, 38 grade II ependymomas, and 28 grade III anaplastic (malignant) ependymomas were differentiated. Grade II ependymomas were predominantly located in the IV ventricle and in the supratentorial midline, which often made complete tumor resection impossible. In contrast, the majority of grade III tumors, most often situated in the cerebral hemispheres, could be totally removed. Operative mortality was higher in grade II than in grade III tumors. After recovery from operation, PFS was mainly determined by the histological grading. Median postoperative PFS was 120 months in grade II, but only 18 months in grade III ependymomas (P = 0.1417). Thus, despite varying therapeutic concepts, analysis of this 40-year collective study confirms the prognostic relevance of localization and WHO grading in the case of intracranial ependymoma in children.