DISEASE CHARACTERISTICS: No more than 1 unresected or subtotally resected brain metastasis lesion from histologically confirmed systemic malignancy Eligible only if surgical resection refused by patient or resection deemed inappropriate by patient's physician 1 intraparenchymal metastasis clearly defined on contrast enhanced MRI Maximum diameter of lesion no greater than 4.0 cm No leukemia or lymphoma Extracranial sites of primary metastatic disease allowed if no clinical or radiographic evidence of progression within 1 month prior to entry No metastasis to brainstem, midbrain, pons, or medulla No leptomeningeal metastasis by MRI or CSF evaluation No metastasis within 10 mm of optic nerves and chiasm (area must be excluded from high dose stereotactic radiosurgery boost field)