Radiation Therapy in Treating Young Patients With Gliomas

RATIONALE: Specialized radiation therapy that delivers radiation directly to the tumor may kill more tumor cells and cause less damage to normal tissue.

PURPOSE: This phase II trial is studying how well radiation therapy works in treating young patients with gliomas.

OBJECTIVES:

Primary

* Determine the marginal-failure rate in young patients with low-grade gliomas treated with reduced-field conformal radiotherapy.

Secondary

* Determine the progression-free survival, event-free survival, and overall survival rates of young patients treated with this regimen.
* Determine quality of life of patients treated with this regimen.
* Correlate MIB-1 labeling index with progression-free survival and overall survival of these patients.

OUTLINE: This is a multicenter study.

Patients undergo reduced-field conformal radiotherapy 5 days a week for 6 weeks in the absence of disease progression or unacceptable toxicity.

Quality of life is assessed at baseline or 6 weeks after completion of study treatment and then at 2 and 5 years (closed as of 10/27/2010).

After completion of study treatment, patients are followed every 3 months for 2 years, every 6 months for 2 years, and then annually thereafter.

Eligibility Criteria:
DISEASE CHARACTERISTICS:

* Histologically confirmed\* low-grade glioma, including any of the following:

  * Juvenile pilocytic astrocytoma (JPA) or pleomorphic JPA
  * Diffuse astrocytoma, including any of the following subtypes:

    * Fibrillary astrocytoma
    * Gemistocytic astrocytoma
    * Subependymal giant cell astrocytoma
    * Pleomorphic xanthoastrocytoma
  * Low-grade oligoastrocytoma
  * Low-grade oligodendroglioma
  * Low-grade glioma not otherwise specified NOTE: \*Patients with chiasmatic lesions who have contiguous extension of tumor into other regions of the visual pathway by CT scan or MRI are eligible without histopathologic confirmation; repeat biopsy required for patients with recurrent tumors that enhance but whose initial tumor did not
* Measurable disease by radiography
* Meets any of the following criteria:

  * Progressive nonresectable disease

    * Any location in the brain
  * Patients with a less than gross total resection are eligible provided they are symptomatic from their tumor OR the risk from neurologic impairment with progression is high enough to warrant immediate treatment
  * Has undergone biopsy only
* Must have received ≥ 1 course of prior chemotherapy (for patients \< 10 years of age)

  * Prior chemotherapy optional (for patients ≥ 10 years of age)
* No type-1 neurofibromatosis
* No evidence of leptomeningeal dissemination

PATIENT CHARACTERISTICS:

Age

* 3 to 20

Performance status

* ECOG 0-2 OR
* Karnofsky 50-100% (for patients \> 16 years of age) OR
* Lansky 50-100% (for patients ≤ 16 years of age)

Life expectancy

* At least 1 year

Hematopoietic

* Absolute neutrophil count ≥ 1,000/mm\^3
* Platelet count ≥ 100,000/mm\^3 (transfusion independent)
* Hemoglobin ≥ 10.0 g/dL (transfusions allowed)

Hepatic

* Not specified

Renal

* Not specified

Other

* Not pregnant
* Negative pregnancy test
* Fertile patients must use effective contraception
* Not in status epilepticus, coma, or requiring assisted ventilation prior to study entry
* Patients with a seizure disorder are eligible provided they are on anticonvulsants AND disease is well controlled

PRIOR CONCURRENT THERAPY:

Biologic therapy

* Not specified

Chemotherapy

* See Disease Characteristics
* Recovered from prior chemotherapy
* No concurrent chemotherapy

Endocrine therapy

* Concurrent dexamethasone allowed provided patient has been on a stable dose for ≥ 2 weeks prior to study entry
* Concurrent dexamethasone allowed for symptoms of increased intracranial pressure

Radiotherapy

* No prior radiotherapy

Surgery

* See Disease Characteristics

Other

* No other concurrent anticancer therapy