Melphalan, Carboplatin, Mannitol, and Sodium Thiosulfate in Treating Patients With Recurrent or Progressive CNS Embryonal or Germ Cell Tumors

PRIMARY OBJECTIVES: I. To determine the maximum tolerated dose (MTD) of intra-arterial (IA) melphalan given with IA carboplatin, osmotic BBBD and delayed intravenous (IV) sodium thiosulfate (STS) in subjects with recurrent or progressive embryonal and germ cell tumors of the CNS. (Phase I) II. To estimate the response rate in subjects with recurrent or progressive CNS embryonal and germ cell tumors treated with IA carboplatin, IA melphalan, osmotic BBBD and delayed IV STS. (Phase II) SECONDARY OBJECTIVES: I. To describe 2-year progression-free survival (PFS) and overall survival (OS) rates in subjects with recurrent or progressive CNS embryonal and germ cell tumors treated with IA carboplatin, IA melphalan, osmotic BBBD and delayed IV STS. (Phase II) II. To describe neuropsychological and audiology outcomes in subjects with recurrent or progressive CNS embryonal and germ cell tumors treated with IA carboplatin, IA melphalan, osmotic BBBD and delayed IV STS. (Phase II) III. To describe the overall toxicity of IA carboplatin and IA melphalan in conjunction with osmotic BBBD and delayed STS chemoprotection in subjects with recurrent or progressive CNS embryonal or germ cell tumors. (Phase II) OUTLINE: This is a phase I, dose-escalation study of melphalan followed by a phase II study. Patients receive mannitol IA over 30 seconds, melphalan IA over 10 minutes, and carboplatin IA over 10 minutes. Patients then receive sodium thiosulfate IV over 15 minutes at 4 and 8 hours after carboplatin. Treatment repeats every 4-6 weeks for up to 12 cycles in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up every 3 months for 1 year, every 6 months for 1 year, and then annually for 3 years.