Purpose

RATIONALE: Drugs used in chemotherapy, such as vincristine, irinotecan, ifosfamide, etoposide, doxorubicin, cyclophosphamide, and dactinomycin, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. Radiation therapy uses high-energy x-rays to kill tumor cells. Giving high-dose combination chemotherapy together with radiation therapy may kill more tumor cells. PURPOSE: This phase III trial is studying how well giving high-dose combination chemotherapy together with radiation therapy works in treating patients with newly diagnosed metastatic rhabdomyosarcoma or ectomesenchymoma.