Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically or cytologically proven pediatric malignancy,
except when there is appearance consistent with brainstem tumor on MRI, a tumor marker
positive for germ cell tumor, or ophthalmologic diagnosis of intraocular retinoblastoma
Failed conventional treatment or conventional therapy is not available Measurable disease
by MRI, CT scan, biochemical tumor markers, cytology, or bone marrow examination

PATIENT CHARACTERISTICS: Age: Not specified Performance status: Lansky 60-100% OR
Karnofsky 60-100% Life expectancy: At least 6 weeks Hematopoietic: Absolute neutrophil
count at least 750/mm3 (between 300-750/mm3, if due to bone marrow infiltration by
malignancy) Platelet count at least 75,000/mm3 (between 20,000-75,000/mm3, if due to bone
marrow infiltration by malignancy) Hepatic: Bilirubin less than 2.0 mg/dL ALT less than 3
times upper limit of normal (ULN) Renal: Creatinine less than 2 times ULN OR Creatinine
clearance at least 70 mL/min Neurologic: No peripheral neuropathy grade 3 or 4 No seizure
disorder in patients without CNS malignancies Other: Not pregnant or nursing Negative
pregnancy tests during study and for 1 month after final dose of thalidomide Fertile
patients must use effective contraception during and for at least 1 month after study

PRIOR CONCURRENT THERAPY: See Disease Characteristics No limit on the number of prior
agents or regimens received Biologic therapy: Prior bone marrow transplantation allowed
Chemotherapy: Recovered from prior chemotherapy No prior thalidomide Endocrine therapy:
Not specified Radiotherapy: Not specified Surgery: At least 4 weeks since prior major
surgery (2 weeks for minor surgery, excluding central venous catheter placement
procedures)