Temozolomide in Treating Adults With Newly Diagnosed Primary Malignant Glioblastoma Multiforme

DISEASE CHARACTERISTICS:

* Histologically proven, newly diagnosed, supratentorial malignant glioblastoma multiforme not requiring immediate radiation therapy
* At least 1 bidimensionally measurable lesion

PATIENT CHARACTERISTICS:

Age:

* 18 and over

Performance status:

* Karnofsky 70-100%

Life expectancy:

* Greater than 12 weeks

Hematopoietic:

* Absolute neutrophil count at least 1500/mm\^3
* Platelet count at least 100,000/mm\^3
* Hemoglobin at least 10 g/dL

Hepatic:

* Bilirubin less than 1.5 times upper limit of normal (ULN)
* SGOT and SGPT less than 2.5 times ULN
* Alkaline phosphatase less than 2 times ULN

Renal:

* BUN less than 1.5 times ULN
* Creatinine less than 1.5 times ULN

Other:

* Must be neurologically stable
* No systemic disease
* No acute infection requiring intravenous antibiotics
* No frequent vomiting
* No other medical condition that would interfere with oral medication intake such as partial bowel obstruction
* No prior or concurrent malignancies except:

  * Surgically cured carcinoma in situ of the cervix
  * Basal or squamous cell carcinoma of the skin
* HIV negative
* No AIDS-related illness
* Not pregnant or nursing
* Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

* No prior biologic therapy
* No concurrent biologic therapy (growth factors or erythropoietin)

Chemotherapy:

* No prior chemotherapy
* No other concurrent chemotherapy

Endocrine therapy:

* Concurrent steroid allowed (must be on stable dose for at least 1 week prior to study)

Radiotherapy:

* No prior radiation therapy
* No prior interstitial brachytherapy
* No prior radiosurgery to the brain
* Not requiring immediate radiation therapy
* No concurrent radiotherapy

Surgery:

* Recovered from any effects of prior surgery
* At least 2 weeks since prior surgical resection

Other:

* No other concurrent investigational drugs