DISEASE CHARACTERISTICS:

* Histologically or cytologically confirmed malignant peripheral nerve sheath tumor

* Malignant schwannoma or neurofibrosarcoma
* Clinical evidence of unresectable or metastatic disease
* Measurable disease
* No known current CNS metastases

PATIENT CHARACTERISTICS:

Age

* 18 and over

Performance status

* Zubrod 0-2

Life expectancy

* Not specified

Hematopoietic

* Absolute neutrophil count greater than 1,500/mm\^3
* Platelet count greater than 100,000/mm\^3

Hepatic

* Bilirubin less than 1.5 times upper limit of normal (ULN)
* SGOT or SGPT less than 1.5 times ULN (5 times ULN for patients with documented liver metastases)

Renal

* Creatinine no greater than 1.5 times ULN
* Creatinine clearance greater than 60 mL/min

Ophthalmic

* No known history of any of the following corneal diseases:

* Dry eye syndrome
* Sjögren's syndrome
* Keratoconjunctivitis sicca
* Exposure keratopathy
* Fuch's dystrophy
* No other active disorders of the cornea

Gastrointestinal

* No gastrointestinal tract disease resulting in an inability to take oral medication or a requirement for IV alimentation
* No active peptic ulcer disease
* No intractable nausea or vomiting
* Able to swallow medications OR receive enteral medications via gastrostomy feeding tube

Other

* Not pregnant or nursing
* Fertile patients must use effective contraception
* No other malignancy within the past 5 years except adequately treated basal cell or squamous cell skin cancer, carcinoma in situ of the cervix, or adequately treated stage I or II cancer currently in complete remission

PRIOR CONCURRENT THERAPY:

Biologic therapy

* More than 28 days since prior biologic therapy for this malignancy

Chemotherapy

* More than 28 days since prior chemotherapy for this malignancy

Endocrine therapy

* Not specified

Radiotherapy

* More than 60 days since prior radiotherapy to the target lesion with subsequent documented progression
* More than 60 days since prior radiofrequency ablation to the target lesion with subsequent documented progression
* No concurrent radiotherapy

Surgery

* At least 3 weeks since prior major surgery and recovered
* No prior surgical procedure affecting absorption

Other

* More than 28 days since prior investigational drugs for this malignancy
* More than 60 days since prior embolization to the target lesion with subsequent documented progression
* No prior epidermal growth factor receptor-targeting therapy
* No concurrent antiretroviral therapy for HIV-positive patients
* No other concurrent investigational or commercial agents or therapies for the malignancy