DISEASE CHARACTERISTICS:

• Meets 1 of the following criteria:

  • Histologically confirmed solid tumor (closed to accrual as of 10/4/2007) that relapsed after or failed to respond to front-line curative therapy and for which no other potentially curative treatment options exist

    • Curative therapy may include surgery, radiotherapy, chemotherapy, or any combination of these modalities

    • Eligible tumor types include, but are not limited to, the following:

      • Rhabdomyosarcoma
      • Other soft tissue sarcomas
      • Ewing's sarcoma family of tumors
      • Osteosarcoma
      • Neuroblastoma
      • Wilms' tumor
      • Hepatic tumors
      • Germ cell tumors

      • Primary brain tumors

        • Histologic confirmation may be waived for brain stem or optic glioma

  • Diagnosis of relapsed or refractory leukemia

    • Patients with refractory or second or greater relapsed leukemia must have > 25% blasts in the bone marrow (M3 bone marrow) with or without active extramedullary disease (except for leptomeningeal disease)
    • Relapsed after or failed to respond to frontline curative therapy and no other potentially curative therapy (e.g., radiotherapy, chemotherapy, or any combination of these modalities) exists
  • Patients with acute promyelocytic leukemia must be refractory to treatment with retinoic acid and arsenic trioxide
  • Patients with Philadelphia chromosome positive chronic myelogenous leukemia must be refractory to imatinib
• No active CNS leukemia (CNS3)

PATIENT CHARACTERISTICS:

Age:

• 2 to 18 (solid tumor patients [closed to accrual as of 10/4/2007])
• 1 to 21 (leukemia patients)

Performance status:

• For patients age 11 to 21:

  • Karnofsky 50-100%

• For patients age 1 to 10:

  • Lansky 50-100%

Life expectancy:

• Not specified

Hematopoietic:

• Platelet count at least 100,000/mm^3 (20,000/mm^3 for leukemia patients)
• Hemoglobin ≥ 8.0 g/dL

Hepatic:

• Bilirubin less than 1.5 times upper limit of normal (ULN)
• SGOT and SGPT less than 2.5 times ULN
• No hepatic dysfunction that would preclude study

Renal:

• Creatinine normal for age OR
• Creatinine clearance at least 60 mL/min
• No renal dysfunction that would preclude study

Other:

• No known severe prior hypersensitivity reaction to agents containing Cremophor EL
• No clinically significant unrelated systemic illness (e.g., serious infections or other organ dysfunction) that would preclude study
• No grade 2 or greater preexisting sensory neuropathy
• More than 2 month since prior and no concurrent evidence of graft vs host disease
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Recovered from all therapy-related acute toxic effects (leukemia patients only)
• Prior epoetin alfa allowed
• At least 3 days since other prior colony-stimulating factors (e.g., filgrastim (G-CSF), sargramostim (GM-CSF), or interleukin-11 (IL-11))
• At least 6 months since prior bone marrow transplantation
• At least 2 months since prior stem cell transplantation or rescue (leukemia patients)
• At least 7 days since prior therapy with a biological agent and hematopoietic growth factor with the exception of erythropoietin
• More than 3 weeks since prior monoclonal antibody therapy (leukemia patients only)
• No concurrent GM-CSF or IL-11
• No concurrent immunotherapy

Chemotherapy:

• See Disease Characteristics
• Recovered from all therapy-related acute toxic effects (leukemia patients only)
• At least 4 weeks since prior chemotherapy (6 weeks for nitrosoureas)
• No other concurrent anticancer chemotherapy

Endocrine therapy:

• Concurrent corticosteroids allowed for the control of symptoms related to tumor-associated edema in patients with brain tumors
• Patients with brain tumors must be on a stable or tapering dose of corticosteroids for 7 days before baseline scan is performed for the purpose of assessing response to study therapy
• Must be on a stable or tapering dose of corticosteroids for 7 days prior to study entry (leukemia patients only)

Radiotherapy:

• See Disease Characteristics
• Recovered from all therapy-related acute toxic effects (leukemia patients only)
• At least 4 weeks since prior radiotherapy
• More than 2 weeks since prior local palliative radiotherapy (leukemia patients only)
• More than 3 months since prior total-body irradiation, craniospinal radiotherapy, or radiotherapy to ≥50% of the pelvis (leukemia patients only)
• More than 6 weeks since prior other substantial bone marrow radiotherapy (leukemia patients only)
• No prior extensive radiotherapy (e.g., craniospinal irradiation, total body irradiation, or radiotherapy to more than half of the pelvis)
• No concurrent anticancer radiotherapy

Surgery:

• See Disease Characteristics

Other:

• Recovered from prior therapy
• At least 30 days since any prior investigational anticancer therapy

• At least 1 week since prior known inhibitors of CYP3A4, including any of the following:

  • Antibiotics (i.e., clarithromycin, erythromycin, or troleandomycin)
  • Anti-HIV agents (i.e, delaviridine, nelfinavir, amprenavir, ritonavir, idinavir, saquinavir, or lopinavir)
  • Anti-fungals (i.e., itraconazole, ketoconazole, fluconazole [doses > 3mg/kg/day], or voriconazole)
  • Anti-depressants (i.e., nefaxodone or fluovoxamine)
  • Calcium channel blockers (i.e., verapamil or diltiazem)
  • Anti-emetics (i.e., aprepitant [Emend®])
  • Miscellaneous agents (i.e., amiodarone)
  • Grapefruit juice
• No other concurrent investigational agents
• No concurrent St. John's Wort
• No concurrent known inhibitors of CYP3A4, including grapefruit juice
• Concurrent other agents inducing CYP3A4 allowed