RATIONALE: Stereotactic radiation therapy can send x-rays directly to the tumor and cause less damage to normal tissue. Radiation therapy uses high-energy x-rays to kill tumor cells. It is not yet known whether stereotactic radiation therapy is more effective with or without whole-brain radiation therapy in treating patients with brain metastases.

PURPOSE: This randomized phase III trial is studying stereotactic radiation therapy and whole-brain radiation therapy to see how well they work compared with stereotactic radiation therapy alone in treating patients with brain metastases.

OBJECTIVES:

Primary

• Compare the overall survival of patients with 1 to 3 cerebral metastases treated with stereotactic radiosurgery with vs without whole-brain radiotherapy.

Secondary

• Compare time to CNS (brain) failure in patients treated with these regimens.
• Compare quality of life, duration of functional independence, and long-term neurocognitive status of patients treated with these regimens.
• Compare post-treatment toxicity in these patients.

OUTLINE: This is a randomized, multicenter study. Patients are stratified according to age (18 to 59 vs 60 and over), extracranial disease (controlled for ≤ 3 months vs controlled for > 3 months), and number of brain metastases (1 vs 2 vs 3). Patients are randomized to 1 of 2 treatment arms.

• Arm I: Patients undergo stereotactic radiosurgery (SRS).
• Arm II: Patients undergo SRS as in arm I. Within 14 days, patients then undergo whole-brain radiotherapy 5 days a week for 2.5 weeks.

Quality of life, functional independence, and neurocognitive status are assessed at baseline, at the beginning of each treatment, at weeks 6 and 12, and then at 6, 9, 12, 16, 24 , 36, 48, and 60 months.

PROJECTED ACCRUAL: A total of 238 patients will be accrued for this protocol.

DISEASE CHARACTERISTICS:

• Diagnosis of cerebral metastases meeting the following criteria:

  • One to three presumed brain metastases

  • Metastases must be from a histologically confirmed extracerebral site (e.g., lung, breast, prostate)

    • Histologic confirmation may have been from the primary tumor site, from another metastatic site (e.g., osseous metastasis, adrenal metastasis), or from the metastatic brain lesion(s)

  • Each lesion must measure less than 3.0 cm by contrast MRI of the brain performed within the past 21 days

  • Lesions must not be within 5 mm of the optic chiasm or within the brainstem

• Eligibility for treatment with gamma knife or linear accelerator-based radiosurgery confirmed by a radiation oncologist

• No primary germ cell tumor, small cell carcinoma, or lymphoma

• No leptomeningeal metastases

• Hormone receptor status not specified

PATIENT CHARACTERISTICS:

• Male or female

• Menopausal status not specified

• ECOG performance status 0-2

• Not pregnant

• Negative pregnancy test

• Fertile patients must use effective contraception

  • Male patients must continue to use contraception for 3 months after the completion of radiotherapy

• No pacemaker or other MRI-incompatible metal in the body

• No known allergy to gadolinium

PRIOR CONCURRENT THERAPY:

• More than 7 days since prior and no concurrent chemotherapy
• No prior cranial radiotherapy
• No prior resection of cerebral metastases
• Concurrent hormonal agents, steroids, and/or anticonvulsants allowed