Low-Dose Radiation and Combination Chemotherapy Following Surgery in Children With Newly Diagnosed Medulloblastoma

OBJECTIVES: * By giving reduced dose craniospinal radiation followed by nine cycles of maintenance chemotherapy comprised of alternating cycles of lomustine, cisplatin, and vincristine alternating with cyclophosphamide and etoposide, we will reduce the late effects of higher dose radiation in children while maintaining the therapeutic efficacy (86% 3-year relapse-free survival) of current standard therapy * To evaluate the late neurotoxic effects of low-dose craniospinal radiotherapy, in terms of cognitive, endocrinologic, and auditory function, in these patients. OUTLINE: This is a multi center study of reduced dose craniospinal radiotherapy and chemotherapy in patients ages 3 - 30 years with newly diagnosed average risk medulloblastoma. * Induction chemoradiotherapy: Beginning within 28 days after complete surgical resection, patients undergo radiotherapy to the craniospinal axis (1800 centigray (cGy)) followed by conformal radiotherapy to the tumor bed (5400 cGy). Patients receive vincristine weekly for 6 weeks. * Maintenance chemotherapy: Beginning 4 weeks after the completion of craniospinal radiation therapy, patients receive two 6-week courses of regimen A as outlined below alternating with one 6-week course of regimen B for a total of 9 courses (AABAABAAB). * Regimen A: Patients receive oral lomustine and cisplatin on day 0 and vincristine on days 0, 7, and 14. * Regimen B: Patients receive cyclophosphamide on days 0 and 1 and etoposide intravenous (IV) on days 0 and 1, followed by oral etoposide on days 14-34. Patients are followed every 3 months for 1 year, every 6 months for 2 years, and then annually thereafter with surveillance neuroimaging using Magnetic Resonance Imaging Scan (MRI scan) and clinical examination. PROJECTED ACCRUAL: A total of 50 patients will be accrued for this study within 3 years.