Inclusion Criteria:  18 years of age or older Either gender Patients must provide informed consent prior to registration Pathologically (histologically or cytologically) proven diagnosis of solid tumor malignancy Brain metastase(s) outside a 5-mm margin around either hippocampus Brain metastase(s) must be visible on contrast-enhanced magnetic resonance imaging (MRI); an allowed exception for patients who had undergone radiosurgery or surgical resection and are planning adjuvant radiotherapy do not have to have visible disease. Patients must have a gadolinium contrast-enhanced three-dimensional MRI scan, whether diagnostic or a MR simulation scan Karnofsky performance status of >= 70 or ECOG >= 2 Patients may have had prior therapy for brain metastasis, including radiosurgery, as long as with hippocampal-sparing, and surgical resection; patients must have completed prior therapy (no specific time lapse between prior treatment and this treatment)  Exclusion Criteria:  Prior external beam radiation therapy to the brain or whole brain radiation therapy, unless radiosurgery with hippocampal-sparing Radiographic evidence of hydrocephalus or other architectural distortion of the ventricular system, including placement of external ventricular drain or ventriculoperitoneal shunt Patients with definitive leptomeningeal metastases Contraindication to magnetic resonance (MR) imaging such as implanted metal devices or foreign bodies Contraindication to gadolinium contrast administration during MR imaging, such as allergy or insufficient renal function