DISEASE CHARACTERISTICS:

* Histologically confirmed supratentorial glioblastoma multiforme by surgical biopsy or resection within 5 weeks of study
* Postoperative residual contrast enhancing tumor and resection tumor cavity together no greater than 60 mm in maximum diameter
* No well-differentiated or anaplastic astrocytomas or multifocal glioma
* No tumors originating in the brainstem
* No residual tumor within 10 mm of optic chiasm
* No recurrent glioblastoma multiforme

PATIENT CHARACTERISTICS:

Age:

* Not specified

Performance status:

* Zubrod 0-1

Life expectancy:

* Not specified

Hematopoietic:

* Hemoglobin greater than 9 g/dL
* Absolute neutrophil count greater than 1,500/mm\^3
* Platelet count greater than 100,000/mm\^3

Hepatic:

* Bilirubin less than 2.0 mg/dL
* Serum glutamate pyruvate transaminase (SGPT) or serum glutamate oxaloacetate transaminase (SGOT) less than 2 times normal

Renal:

* Creatinine less than 1.8 mg/dL
* Blood urea nitrogen (BUN) less than 30 mg/dL

Pulmonary:

* Chest x-ray normal OR
* Diffusion capacity of lung for carbon monoxide (DLCO) greater than 60% predicted

Other:

* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception
* Neurologic functional status 0-3
* No other prior malignancy within the past 5 years except carcinoma in situ of the cervix or bladder, ductal carcinoma in situ of the breast, or nonmelanomatous skin cancer

PRIOR CONCURRENT THERAPY:

Biologic therapy:

* Not specified

Chemotherapy:

* Not specified

Endocrine therapy:

* Concurrent steroids allowed

Radiotherapy:

* Not specified

Surgery:

* See Disease Characteristics

Other:

* Concurrent anticonvulsants allowed