RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Combining chemotherapy with peripheral stem cell transplantation may allow the doctor to give higher doses of chemotherapy drugs and kill more tumor cells. Chemoprotective drugs such as amifostine may protect normal cells from the side effects of high-dose chemotherapy.

PURPOSE: Phase I trial to study the effectiveness of amifostine in protecting from the side effects of peripheral stem cell transplantation in treating patients who have high-risk or relapsed 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.

• Brain and Central Nervous System Tumors
• Cancer-related Problem/Condition
• Childhood Germ Cell Tumor
• Chordoma
• Extragonadal Germ Cell Tumor
• Kidney Cancer
• Liver Cancer
• Neuroblastoma
• Ovarian Cancer
• Retinoblastoma
• Sarcoma
• Testicular Germ Cell Tumor

• Drug: amifostine trihydrate
• Drug: busulfan
• Drug: filgrastim
• Drug: melphalan
• Drug: thiotepa
• Procedure: peripheral blood stem cell transplantation

DISEASE CHARACTERISTICS:

• Histologically confirmed high-risk or relapsed solid tumors or brain tumors, including:

  • Metastatic or relapsed Ewing's sarcoma
  • Metastatic or relapsed rhabdomyosarcoma
  • Refractory Wilms' tumor
  • Diffuse anaplastic Wilms' tumor
  • Stage III or IV neuroblastoma
  • Recurrent retinoblastoma
  • Metastatic or relapsed germ cell tumors
  • Metastatic or relapsed other soft tissue sarcomas
  • Small cell ovarian sarcoma
  • Metastatic or relapsed primitive neuroectodermal tumors of the bone
  • Recurrent brain tumors
  • Desmoplastic small round cell tumors
  • Recurrent or metastatic chordomas
  • Metastatic or relapsed hepatoblastoma
• No osteogenic sarcoma
• Patients receive peripheral blood stem cell transplantation only if in complete remission or in very good partial remission with no disease progression
• Must have radiologic, nuclear image, or histologic verification of relapse

PATIENT CHARACTERISTICS:

Age:

• 1 to 45

Performance status:

• Karnofsky 70-100%

Life expectancy:

• More than 4 months

Hematopoietic:

• No uncontrolled bleeding
• Absolute neutrophil count greater than 1,000/mm^3
• Platelet count greater than 100,000/mm^3
• Hemoglobin count at least 10 g/dL

Hepatic:

• Bilirubin less than 2 times upper limit of normal (ULN)
• SGOT or SGPT less than 2.5 times ULN

Renal:

• Creatinine less than 2 times ULN
• Creatinine clearance greater than 70 mL/min

Cardiovascular:

• Cardiac shortening fraction greater than 30%
• Cardiac ejection fraction greater than 45%
• No congestive heart failure
• No uncontrolled hypertension

Pulmonary:

• No asthma

Other:

• Not pregnant or nursing
• No uncontrolled metabolic disease
• No active severe infection
• No allergy to aminothiol compounds

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• At least 1 week since prior hematopoietic growth factor and recovered
• No prior bone marrow transplantation

Chemotherapy:

• At least 3 weeks since prior chemotherapy (6 weeks for nitrosoureas) and recovered

Endocrine therapy:

• Not specified

Radiotherapy:

• Not specified

Surgery:

• Not specified

Other:

• Recovered from any prior therapy
• No other concurrent investigational agents