Inclusion Criteria:

All patients must have histological verification of malignancy at original diagnosis.

- Eligible Diseases

- Ewing's Family Tumors (ES/PNET/DSRCT) - metastatic at time of diagnosis and/or
relapsed after therapy

- Renal Tumors - relapsed (all histology - Wilm's tumor) or at diagnosis (clear
cell sarcoma and Rhabdoid tumor)

- Hepatoblastoma - metastatic at time of diagnosis and/or relapsed after therapy

- Rhabdomyosarcoma - metastatic at time of diagnosis and/or relapsed after therapy

- Soft Tissue Sarcoma - chemotherapy responsive metastatic disease or chemotherapy
responsive relapsed disease

- Primary Malignant Brain Neoplasms <18 years of age - at diagnosis and/or relapse

- Retinoblastoma - disseminated at diagnosis and/or relapsed

- Other High Risk Metastatic or Relapsed Solid Tumors - to be approved by 2 or
more pediatric hematology/oncology and bone marrow transplant (BMT) physicians

- Disease Status at Enrollment must have fit one of the following:

- no evidence of disease or

- stable, non-progressive disease (defined as non-progressive abnormalities on
physical exam or CT and/or MRI) within 4 weeks of study entry

- Age and Performance Status

- Age: 0 - 70 years

- Performance status: Karnofsky Performance Status at least 50% for patients > 16
years of age or Lansky Play Score at least 50 for patients less than or equal to
16 years of age. (Note: Neurologic deficits in patients with central nervous
system (CNS) tumors must be stable for a minimum of 1 week prior to study entry

- Organ Function

- Hematologic: hemoglobin of >9 gm/dl and platelet count > 20,000/μl. Patients may
receive transfusions as necessary.

- Renal: Glomerular Filtration Rate (GFR) ≥ 50 ml/min/1.73m2 or serum creatinine ≤
2.5 x upper limit of normal (ULN) for age

- Hepatic: aspartate aminotransferase or alanine aminotransferase (AST or ALT) ≤ 5
x ULN and bilirubin ≤ 5 x ULN

- Cardiac: ejection fraction ≥ 45% or no clinical evidence of heart failure

- Pulmonary: oxygen saturation > 92% at rest (on room air)

Exclusion Criteria:

- Pregnant or breastfeeding

- Active, uncontrolled infection and/or human immunodeficiency virus (HIV) positive