Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed high-risk rhabdomyosarcoma or ectomesenchymoma

- Prior enrollment on COG-D9902 to confirm local histological diagnosis required

- Tissue must be submitted for pathologic review within 2 days of patient
registration on COG-D9902

- Newly diagnosed disease

- Metastatic disease (stage IV, clinical group IV)

- Has undergone initial surgical procedure (including biopsy) that provided the
definitive diagnosis within the past 42 days

- Parameningeal and paraspinal tumors allowed

- Patients with parameningeal (without intracranial extension [ICE]) and
paraspinal tumors should begin study chemotherapy at week 1 and radiotherapy at
week 20

- Patients with evidence of ICE, as defined by contrast MRI showing that primary tumor
touches, displaces, invades, distorts, or otherwise causes a signal abnormality of
the dura in contiguity to the primary site in brain or spinal cord, are eligible

- ICE is presumed to exist if the cerebrospinal fluid cytopathology is positive
for tumor at diagnosis

- Patients requiring emergency radiotherapy are eligible

- Patients requiring emergency radiotherapy (for intracranial extension or spinal
cord impingement) should begin study chemotherapy at week 1 (irinotecan
hydrochloride and vincristine) concurrently with radiation therapy

PATIENT CHARACTERISTICS:

- ECOG or Zubrod performance status (PS) 0-2 (Lansky PS 50-100% for patients < 10 years
of age and Karnofsky PS 50-100% for patients ≥ 10 years of age)

- Absolute neutrophil count ≥ 750/mm³*

- Platelet count ≥ 75,000/mm³*

- Creatinine clearance or radioisotope glomerular filtration rate ≥ 70 mL/min (≥ 40
mL/min for infants < 1 year of age)

- Patients with urinary tract obstruction by tumor must meet the renal function
criteria listed above AND must have unimpeded urinary flow established via
decompression of the obstructed portion of the urinary tract

- SGPT < 2.5 times normal

- Bilirubin < 1.5 mg/dL

- Shortening fraction ≥ 27% by echocardiogram OR ejection fraction ≥ 50% by MUGA

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception during study and for ≥ 1 month
after study completion

- No evidence of uncontrolled infection

- Able to undergo radiotherapy NOTE: *Abnormal blood counts allowed if there is bone
marrow biopsy or aspirate proven bone marrow involvement by rhabdomyosarcoma

PRIOR CONCURRENT THERAPY:

- No prior chemotherapy except steroids

- No prior radiotherapy

- No concurrent aprepitant during ifosfamide or doxorubicin hydrochloride chemotherapy

- No concurrent dexrazoxane

- No concurrent sargramostim (GM-CSF) or pegfilgrastim