Combination Chemotherapy, Radiation Therapy, and an Autologous Peripheral Blood Stem Cell Transplant in Treating Young Patients With Atypical Teratoid/Rhabdoid Tumor of the Central Nervous System

PRIMARY OBJECTIVES: I. To determine the 6-, 12-, and 24-month event-free survival and overall survival of children (birth to 21 years of age) with atypical teratoid/rhabdoid CNS tumors (AT/RT), diagnosed based on histology, immunophenotyping, and modern molecular and immunohistochemical analysis of INI1, treated with surgery, intensive chemotherapy combined with stem cell rescue, and radiation therapy. II. To compare the outcome of very young patients (under 3 years old) on this study whose histologic diagnosis is AT/RT with infants identified as having AT/RT on POG-9233 and CCG-9921. SECONDARY OBJECTIVES: I. To determine the feasibility and toxicity of the proposed chemotherapy regimen in combination with radiation therapy. II. To contribute tumor samples from which biologic and gene expression data can be developed to yield prognostic indicators and provide direction for future treatment strategies. III. To develop a clinical and biologic database on which future studies can be based. OUTLINE: INDUCTION THERAPY AND STEM CELL HARVEST: Patients receive vincristine IV on days 1, 8, and 15 and high-dose methotrexate IV over 4 hours on day 1. Beginning 24 hours after the start of methotrexate, patients receive leucovorin calcium orally (PO) or IV every 6 hours until the serum methotrexate level is \< 0.1 micromoles. Patients then receive etoposide IV over 1 hour on approximately days 4, 5, and 6, cyclophosphamide IV over 1 hour on approximately days 4 and 5, and cisplatin IV over 6 hours on approximately day 6\*. Patients also receive filgrastim (G-CSF) IV or subcutaneously (SC) once daily beginning on day 7 and continuing until ANC recovers. When ANC is \> 1,000/uL post nadir, patients receive G-CSF twice daily for stem cell mobilization. Approximately 2-4 days, later peripheral blood stem cells are harvested once daily, as needed, after each course of induction therapy until a total of 6 x 10\^6 CD34+ cells/kg have been collected. Treatment repeats every 21 days for 2 courses. After completion of induction therapy, patients are re-evaluated. Patients with progressive disease are removed from study. Patients with radiographic evidence of residual tumor are encouraged to undergo second-look surgery prior to proceeding to radiotherapy or consolidation therapy; patients with complete response, partial response, or stable disease are assigned to 1 of 2 arm. ARM I ((patients less than 6 months, infratentorial site with M0 involvement or patients less than 12 months, supratentorial site with M0 involvement or patients with disseminated disease of any primary site or age): CONSOLIDATION THERAPY AND STEM CELL RESCUE: Within 2-6 weeks after completion of induction therapy, patients begin consolidation therapy. Patients receive high-dose carboplatin IV over 4 hours and high-dose thiotepa IV over 2 hours on days 1 and 2 and undergo autologous peripheral blood stem cell (PBSC) rescue on approximately day 4. Patients also receive G-CSF IV or SC once daily beginning 24 hours after stem cell infusion and continuing until ANC recovers. Treatment with consolidation therapy followed by stem cell rescue repeats every 28 days for 3 courses in the absence of disease progression or unacceptable toxicity. RADIATION THERAPY: Patients undergo 3-dimensional conformal radiotherapy (3D-CRT) to the brain (and the spine if needed) 5 days a week for 5-6 weeks. ARM II (patients greater than or equal to 6 months, infratentorial site with M0 involvement or patients greater than or equal to 12 months, supratentorial site with M0 involvement): Patients undergo 3D-CRT as in Arm I. Within 2-6 weeks after completion of radiation therapy, patients receive consolidation therapy and stem cell rescue as in Arm I NOTE: \*The administration of etoposide, cyclophosphamide, and cisplatin are dependant on the prior clearance of methotrexate to a level of \< 0.1 micromoles. After completion of study treatment, patients are followed periodically for up to 10 years.