Stereotactic Radiosurgery in Treating Patients With Large Brain Metastases

Inclusion Criteria: * Any patient undergoing SRS for brain metastases * Lesions to be treated under this protocol must be \> 2 cm, but =\< 4.0 cm in diameter * Patients may have had prior therapy including: * Whole brain radiation therapy (WBRT) \> 3 months ago * SRS to other brain metastases * Patients with newly diagnosed brain metastases are eligible as long as they are not planned for WBRT upfront * Any primary is eligible with exception of small cell lung cancer, lymphoma, and germ cell histologies * Patient must be able to provide written informed consent Exclusion Criteria: * Patients receiving SRS to resection bed * Planned concurrent WBRT * Leptomeningeal metastases * Small cell lung cancer, lymphoma, and germ cell histologies * Inability to participate in study activities due to physical or mental limitations * Inability or unwillingness to return for all the required follow-up visits * Conformality index 2.0 or less cannot be achieved, or homogeneity index is \> 2.0 * Unable to deliver 10 Gray (Gy) or less to optic nerve/chiasm * Brainstem location is excluded from this study