PRIMARY OBJECTIVE:~I. To ascertain if the composite endpoint of cumulative treatment failure, defined by time to either local failure or symptomatic radiation brain necrosis of the largest brain metastasis (target lesion), is increased with fractionated stereotactic radiosurgery (FSRS) compared to single fraction stereotactic radiosurgery (SSRS).~SECONDARY OBJECTIVES:~I. To ascertain whether there is improved overall survival in patients who undergo FSRS compared to patients who receive SSRS.~II. To tabulate and descriptively compare the post-treatment adverse events associated with the interventions, including the potential impact of immunotherapy and targeted therapy.~III. To compare rates of radiation necrosis in patients who receive FSRS to patients who receive SSRS.~IV. To evaluate if there is any difference in central nervous system (CNS) failure patterns (e.g. local, distant brain failure) in patients who receive FSRS compared to patients who receive SSRS.~V. To ascertain whether FSRS prolongs time to neurologic death as compared to SRS.~VI. To determine whether there is improved patient reported outcomes (Functional Assessment of Cancer Therapy [FACT]-Brain Symptom Index [FBrSI]-24) including quality of life for patients who receive FSRS compared to patients who receive SSRS.~VII. To evaluate if there is any difference in CNS failure patterns (e.g. local, distant brain failure) and symptomatic radiation necrosis rates in patients who are treated with gamma knife compared to patients who are treated with a linear accelerator platform.~VIII. To determine whether differences in time to local failure, time to necrosis, or their composite endpoint cumulative treatment failure differs between treatment arms (or other patient or treatment factors) when analyzed on a per lesion basis rather than the per patient basis utilized for the primary endpoint.~OUTLINE: Patients are randomized to 1 of 2 arms.~ARM A: Patients undergo single fraction SRS.~ARM B: Patients undergo fractionated SRS.~After completion of study treatment, patients are followed up at 3 months, every 3 months for 2 years, and then every 6 months for 3 years.
This phase II trial compares the effect of single fraction stereotactic radiosurgery to fractionated stereotactic radiosurgery for the treatment of patients with cancer that has spread to the brain (metastatic brain disease). Stereotactic radiosurgery (SRS) is a form of radiation therapy that focuses high-power energy on a small area of the body. This trial is being done to determine if single (one) fraction stereotactic radiosurgery is better than fractionated stereotactic radiosurgery or vice versa in controlling tumor and side effects in patients with tumors that have spread to the brain.