SRS and Nivolumab in Treating Patients With Newly Diagnosed Melanoma Metastases in the Brain or Spine

PRIMARY OBJECTIVES: I. To assess the safety profile of stereotactic radiosurgery with nivolumab in combination to treat patients with newly diagnosed melanoma brain or spinal metastases. SECONDARY OBJECTIVES: I. To estimate local control rate in brain and spine. II. To estimate systematic control rate. III. To estimate progression-free survival. TERTIARY OBJECTIVES: I. To explore peripheral blood immune response during and after treatment. OUTLINE: Patients receive nivolumab intravenously (IV) over 60 minutes on day 1. Patients then undergo stereotactic radiosurgery on day 8 per standard of care. Courses with nivolumab repeats every 14 days in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up at 30 days, every 10 weeks, and then every 3 months thereafter.