Etoposide in Treating Young Patients With Relapsed Ependymoma

DISEASE CHARACTERISTICS: Histologically confirmed intracranial ependymoma at first, second, or third relapse Anaplastic (malignant) or low-grade ependymoma (cellular, papillary, clear cell, or mixed variants) Unequivocal evidence of tumor recurrence or progression by MRI scan after failing conventional treatment (e.g., primary surgery and adjuvant radiotherapy) for initial or recurrent disease Unresectable disease OR not amenable to complete surgical resection Measurable enhancing or non-enhancing disease on baseline scan performed within the past 2 weeks Patients who have undergone prior surgery must have residual measurable disease PATIENT CHARACTERISTICS: Lansky performance status 30-100% Life expectancy ≥ 8 weeks Absolute neutrophil count > 1,000/mm^3 Platelet count > 100,000/mm^3 Serum total bilirubin normal AST < 2 times upper limit of normal No unrelated medical condition (e.g., renal or liver impairment) that would preclude chemotherapy treatment No active infection No known HIV positivity PRIOR CONCURRENT THERAPY: See Disease Characteristics No radiotherapy within the past 6 weeks No chemotherapy within the past 4 weeks Prior IV etoposide allowed