Stereotactic Radiosurgery or Whole-Brain Radiation Therapy in Treating Patients With Brain Metastases That Have Been Removed By Surgery

Primary Goals 1. Overall Survival - To determine in patients with one to four brain metastases whether there is improved overall survival in patients who receive SRS to the surgical bed compared to patients who receive WBRT. 2. Neurocognitive Progression - To determine in patients with one to four brain metastases whether there is less neurocognitive progression post-randomization in patients who receive SRS to the surgical bed compared to patients who receive WBRT. Secondary Goals 1. Quality of Life (QOL) - To determine in patients with resected brain metastases whether there is improved QOL in patients who receive SRS to the surgical bed compared to patients who receive WBRT. 2. Central Nervous System Failure - To determine in patients with one to four brain metastases whether there is equal or longer time to central nervous system (CNS) failure (brain) in patients who receive SRS to the surgical bed compared to patients who receive WBRT. 3. Functional Independence - To determine in patients with one to four brain metastases whether there is longer duration of functional independence in patients who receive SRS to the surgical bed compared to patients who receive WBRT. 4. Long-Term Neurocognitive Status - To determine in patients with one to four brain metastases whether there is better long-term neurocognitive status in patients who receive SRS to the surgical bed compared to patients who receive WBRT. 5. Adverse Events - To tabulate and descriptively compare the post-treatment adverse events associated with the interventions. 6. Local Tumor Bed Recurrence - To evaluate local tumor bed recurrence at 6 months with post-surgical SRS to the surgical bed in comparison to WBRT. 7. Local Recurrence - To evaluate time to local recurrence with post-surgical SRS to the surgical bed in comparison to WBRT. 8. CNS Failure Patterns - To evaluate if there is any difference in CNS failure patterns (local, distant, leptomeningeal) in patients who receive SRS to the surgical bed compared to patients who receive WBRT. OUTLINE: This is a multicenter study. Patients are stratified according to age in years (\< 60 vs ≥ 60), extracranial disease controlled (≤ 3 months vs \> 3 months), number of pre-operative brain metastases (1 vs 2-4), histology (lung vs radioresistant \[brain metastases from a sarcoma, melanoma, or renal cell carcinoma histology\] vs other), and resection cavity maximal diameter (≤ 3 cm vs \> 3 cm). Patient must complete baseline QOL and neurocognitive tests prior to registration/randomization. Patients are randomized to 1 of 2 treatment arms. * Arm I: Patients undergo whole-brain radiotherapy (WBRT) once a day, 5 days a week, for approximately 3 weeks. * Arm II: Patients undergo stereotactic radiosurgery (SRS) using a gamma knife or a linear accelerator procedure. Event monitoring occurs up to 5 years post registration/randomization.