Radiation Therapy in Treating Patients With Newly Diagnosed Brain Metastases From Kidney Cancer, Melanoma, or Sarcoma

DISEASE CHARACTERISTICS: * Histologically confirmed renal cell carcinoma, melanoma, or sarcoma with 1-3 newly diagnosed intraparenchymal brain metastases based on contrast-enhanced MRI (CT scan acceptable if patients have a medical contraindication to MRI) * No lesion greater than 4.0 cm in diameter and, if multiple lesions are present, no more than one greater than 3.0 cm in diameter * No limitation on the extent of extracranial metastatic disease * No metastases in the brain stem, midbrain, pons, or medulla * No leptomeningeal metastases documented by MRI or CSF evaluation * No metastases within 10 mm of optic nerve or chiasm * No history of multiple liver metastases PATIENT CHARACTERISTICS: Age: * 18 and over Performance status: * ECOG 0-2 Life expectancy: * At least 3 months Hematopoietic: * Absolute neutrophil count greater than 1,000/mm\^3 * Platelet count greater than 50,000/mm\^3 * Hemoglobin greater than 8 g/dL Hepatic: * Not specified Renal: * Not specified Other: * No major medical illness * No psychoses * Not pregnant or nursing * Fertile patients must use effective contraception PRIOR CONCURRENT THERAPY: Biologic therapy: * Not specified Chemotherapy: * Prior chemotherapy allowed * Systemic chemotherapy may be continued at the discretion of investigator after completion of radiosurgery Endocrine therapy: * Not specified Radiotherapy: * No prior cranial radiotherapy * Prior or concurrent radiotherapy to noncranial sites allowed Surgery: …