Combination Chemotherapy in Treating Patients With Stage III or Stage IV Malignant Peripheral Nerve Sheath Tumors

DISEASE CHARACTERISTICS: * Newly diagnosed sporadic or neurofibromatosis type 1 (NF1)-associated high-grade malignant peripheral nerve sheath tumors (MPNSTs) * Stage III or stage IV (metastatic) disease * Measurable disease, defined as at least 1 tumor that is measurable in 2 dimensions on CT scan or MRI PATIENT CHARACTERISTICS: * Ejection fraction normal by echocardiogram or MUGA * Serum creatinine normal for age OR creatinine clearance \> 60 mL/min * SGPT \< 5 times upper limit of normal (ULN) * Bilirubin \< 2.5 times ULN * Absolute neutrophil count ≥ 1,500/mm\^3\* * Hemoglobin ≥ 9.0 g/dL\* * Platelet count ≥ 100,000/mm\^3\* * ECOG performance status 0-2 * Not pregnant or nursing * Negative pregnancy test * Fertile patients must use effective contraception during and for 6 months after completion of study treatment NOTE: \* Unsupported PRIOR CONCURRENT THERAPY: * No prior chemotherapy for MPNST * Prior surgical resection of MPNST allowed provided residual or recurrent measurable disease is present * Recovered from toxic effects of all prior therapy * At least 3 weeks since prior chemotherapy or biologic therapy for treatment of a plexiform neurofibroma, optical pathway tumor, or other NF1-associated tumor (in patients with NF1) * At least 6 weeks since prior radiotherapy for treatment of a plexiform neurofibroma, optical pathway tumor, or other NF1-associated tumor (in patients with NF1) * At least 4 weeks since prior radiotherapy to the area involved by MPNST * No …