Amifostine to Protect From Side Effects of PSCT in Treating Patients With Solid Tumors

OBJECTIVES: * Determine the dose-limiting toxicity of amifostine chemoprotection with peripheral blood stem cell transplantation plus chemotherapy in patients with high-risk or relapsed solid tumors or brain tumors. * Determine response or time to disease progression in patients treated with this regimen. OUTLINE: This is a dose-escalation study of amifostine. Patients are stratified according to age (1 to 18 vs 19 to 45 years). All patients receive filgrastim (G-CSF) IV for 1 week. On day 6 of G-CSF administration, patients undergo peripheral blood stem cell (PBSC) harvest followed by chemotherapy. Patients receive oral busulfan every 6 hours on days -8 to -6 followed by melphalan IV over 30 minutes on days -5 and -4 and thiotepa IV over 2 hours on days -3 and -2. Patients receive amifostine IV over 5 minutes beginning 30 minutes prior to melphalan and thiotepa administration on days -5 to -1. PBSC are reinfused on day 0. Cohorts of 3-6 patients receive escalating doses of amifostine until the maximum tolerated dose is determined. The MTD is defined as the dose preceding that at which 2 of 3 or 2 of 6 patients experience dose-limiting toxicity. Patients are followed on day 50; at 3, 6, and 9 months; and at 1, 2, and 3 years post PBSC transplantation. PROJECTED ACCRUAL: A maximum of 60 patients (30 per stratum) will be accrued for this study within 3 years.