A Phase II Trial of Preradiation in Multiagent Chemotherapy for Adults With "Poor Risk" Medulloblastoma, PNET, and Disseminated Ependymoma

Histologically verified CNS neoplasms including: medullablastoma w/either local residual dz following resection of > 1 cm2 on MRI or evidence of met. M1-M4; other PNET; or ependymoma w/evidence of subarachnoid met.; no prior h/o chemo or RT; must not be on increasing dose of steroids for intracranial dz w/i 3 days of registration; must be > 10 days and < 28 days from date of srg. at the time of registration; pt. having only a biopsy can be entered at 5 days post-srg; pt. must have < 1 cm of midline shift or no acute elevated intercranial pressure which may be worsened by required hydration.