Trabectedin in Treating Young Patients With Recurrent or Refractory Soft Tissue Sarcoma or Ewing's Family of Tumors

Inclusion Criteria:

* Patients must be greater than or equal to 12 months of age at the time of study entry and no more than 21 years of age when initially diagnosed with the malignancy to be treated on this protocol
* Histologically confirmed recurrent or refractory sarcoma tumors, including the following:

  * Rhabdomyosarcoma
  * Nonrhabdomyosarcomatous soft tissue sarcoma
  * Ewing's sarcoma
* Measurable disease by imaging studies

  * Lesions assessable only by radionuclide scans are not considered measurable
  * If the only measurable lesion has been previously irradiated, then that lesion must have shown evidence of an interim increase in size
* No significant amount of metastatic liver disease, defined as the following:

  * Lesions occupying more than 25% of the liver by imaging and abnormal liver function tests or abnormal synthetic liver function
* Performance status - Lansky 50-100% (10 years of age and under)
* Performance status - Karnofsky 50-100% (over 10 years of age)
* Absolute neutrophil count at least 1,000/mm\^3
* Platelet count at least 100,000/mm\^3 (transfusion independent)
* Hemoglobin at least 8.0 g/dL (transfusion allowed)
* No concurrent CYP3A4 inhibitors, including the following:

  * Grapefruit juice
  * Erythromycin
  * Azithromycin
  * Clarithromycin
  * Rifampin and its analogs
  * Fluconazole
  * Ketoconazole
  * Itraconazole
  * Cimetidine
  * Cannabinoids (marijuana or dronabinol)
  * Leukotriene inhibitors used in asthma (e.g., zafirlukast, montelukast, or zileuton)
* Bilirubin no greater than upper limit of normal (ULN)
* Total alkaline phosphatase no greater than ULN
* Hepatic fraction alkaline phosphatase and 5 nucleotidase no greater than ULN
* SGOT and SGPT ≤ 2.5 times ULN
* Albumin ≥ 2.5 g/dL
* Gamma-glutamyl transferase \< 2.5 times ULN
* Maximum creatinine based on age as follows:

  * 0.8 mg/dL (5 years of age and under)
  * 1.0 mg/dL (6 to 10 years of age)
  * 1.2 mg/dL (11 to 15 years of age)
  * 1.5 mg/dL (over 15 years of age)
* Creatinine clearance or radioisotope glomerular filtration rate (GFR) at least 70 mL/min
* No uncompensated congestive heart failure within the past 6 months
* Not pregnant or nursing
* Fertile patients must use effective contraception during and for 2 months after study participation
* No active uncontrolled infection
* Weight ≥ 15 kilograms
* More than 1 week since prior growth factors that support platelet or white blood cell number or function
* At least 7 days since prior biologic agents and recovered
* No prior allogeneic stem cell transplantation
* No other concurrent immunomodulating agents
* More than 3 weeks since prior myelosuppressive chemotherapy (4 weeks for nitrosoureas) and recovered
* No more than 2 prior multi-agent chemotherapy regimens
* No other concurrent anticancer chemotherapy
* Concurrent steroids allowed
* At least 6 weeks since prior since prior extended radiotherapy and recovered
* No prior total body radiotherapy
* Concurrent radiotherapy to localized painful lesions allowed provided at least 1 measurable lesion is not irradiated\*
* At least 7 days since prior enzyme-inducing anticonvulsants (e.g., carbamazepine, phenobarbital, or phenytoin)
* No concurrent enzyme-inducing anticonvulsants
* No other concurrent investigational agents