DISEASE CHARACTERISTICS:

• Histologically proven recurrent or unresectable:
• Malignant meningioma
• Intracranial hemangiopericytoma
• Primary central nervous system sarcoma, including:
• Fibrosarcoma
• Rhabdomyosarcoma
• Chondrosarcoma
• Leiomyosarcoma
• Measurable or evaluable disease on CT or MRI scan
• Persistent disease following biopsy or incomplete resection OR
• Recurrent disease following complete resection
• No benign meningioma
• No prior or current systemic sarcoma

PATIENT CHARACTERISTICS:

Age:

• 18 and over

Performance status:

• SWOG 0-2

Life expectancy:

• Not specified

Hematopoietic:

• WBC at least 3,000/mm^3
• Absolute granulocyte count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3

Hepatic:

• Not specified

Renal:

• Creatinine no greater than 2.0 mg/dL

Cardiovascular:

• No myocardial infarction within the past 3 months
• No active angina
• No unstable heart rhythms
• No congestive heart failure

Other:

• HIV negative
• No allergy to study drugs
• No serious concurrent medical or psychiatric illness
• No uncontrolled peptic ulcer disease
• No prior malignancy within past 5 years except adequately treated:
• Basal or squamous cell carcinoma of the skin
• Carcinoma in situ of the cervix
• Not pregnant or nursing
• Effective contraception required of fertile patients

PRIOR CONCURRENT THERAPY:

• Recovered from toxic effects of prior therapy and/or from postoperative complications

Biologic therapy:

• Not specified

Chemotherapy:

• No prior ifosfamide
• No other concurrent chemotherapy

Endocrine therapy:

• No concurrent hormonal therapy (except estrogen replacement therapy)
• Corticosteroids allowed if dose is stable or decreasing

Radiotherapy:

• At least 4 weeks since prior radiotherapy
• Progressive disease following radiation required
• No concurrent radiotherapy

Surgery:

• See Disease Characteristics