RATIONALE: Radiation therapy uses high-energy x-rays to kill tumor cells. Erlotinib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth and by blocking blood flow to the tumor. It may also make tumor cells more sensitive to radiation therapy. Giving radiation therapy together with erlotinib may kill more tumor cells.

PURPOSE: This phase I/II trial is studying the side effects and best dose of erlotinib when given together with radiation therapy and to see how well they work in treating patients with newly diagnosed glioma.

OBJECTIVES: Primary

• Determine the maximum tolerated dose and dose-limiting toxicity of erlotinib when administered during and after radiotherapy in young patients with newly diagnosed intracranial high-grade glioma and unfavorable low-grade glioma.
• Determine the 1- and 2-year progression-free survival of patients treated with this regimen.

Secondary

• Determine the toxic effects of this regimen in these patients.
• Correlate genetic abnormalities in epidermal growth factor receptor (EGFR) and components of downstream pathways with treatment response in patients treated with this regimen.
• Determine the ability of erlotinib to inhibit EGFR signaling in patients with high-grade glioma who require second surgery.
• Determine the pharmacokinetics of erlotinib and its metabolites in these patients.
• Correlate plasma and cerebrospinal fluid levels of vascular endothelial growth factor and basic fibroblast growth factor with tumor response in patients treated with this regimen.
• Correlate irradiation dosimetry with patterns of failure, standard and investigational imaging, and toxicity in patients treated with this regimen.

OUTLINE: This is a phase I dose-escalation study of erlotinib followed by a phase II study.

• Patients undergo radiotherapy once daily, 5 days week, for approximately 6½ weeks. Beginning on the first day of radiotherapy, patients receive oral erlotinib once daily for 52 weeks. Cohorts of patients receive escalating doses of erlotinib until the maximum tolerated dose (MTD) is determined.
• Phase II: Patients will receive erlotinib as in phase I at the MTD and undergo radiotherapy as in phase I.

PROJECTED ACCRUAL: A total of 75-80 patients (15-20 for the phase I portion and 60 for the phase II portion) will be accrued for this study.

DISEASE CHARACTERISTICS:

• Diagnosis of intracranial glioma of 1 of the following types:
• Unfavorable low-grade glioma
• Gliomatosis cerebri or bithalamic involvement
• Histologically confirmed high-grade glioma (WHO grade III or IV) of 1 of the following subtypes:
• Anaplastic astrocytoma
• Anaplastic oligodendroglioma
• Anaplastic oligoastrocytoma
• Anaplastic ganglioglioma
• Pleomorphic xanthoastrocytoma with anaplastic features
• Malignant glioneuronal tumor
• Glioblastoma multiforme
• Gliosarcoma
• Newly diagnosed disease

PATIENT CHARACTERISTICS: Age

• 3 to 25

Performance status

• Karnofsky 40-100% (age 17 to 25 years) OR
• Lansky 40-100% (age 3 to 16 years)

Life expectancy

• Not specified

Hematopoietic

• Absolute neutrophil count ≥ 1,000/mm^3
• Platelet count ≥ 100,000/mm^3 (transfusion independent)
• Hemoglobin ≥ 8 g/dL (transfusion allowed)

Hepatic

• Bilirubin < 1.5 times upper limit of normal (ULN)
• SGPT < 5 times ULN
• Albumin ≥ 2 g/dL

Renal

• Creatinine < 2 times normal OR
• Glomerular filtration rate > 70 mL/min

Cardiovascular

• No significant cardiovascular problem

Pulmonary

• No significant pulmonary problem

Other

• Not pregnant or nursing
• Fertile patients must use effective contraception
• No uncontrolled infection
• No significant medical illness

PRIOR CONCURRENT THERAPY: Biologic therapy

• No prior or concurrent biologic agents

Chemotherapy

• No prior or concurrent chemotherapy

Endocrine therapy

• Not specified

Radiotherapy

• No prior radiotherapy

Surgery

• No more than 42 days since prior surgery

Other

• No prior or other concurrent anticancer or experimental treatment
• At least 7 days since prior enzyme-inducing anticonvulsants