Stereotactic Body Radiotherapy for Spine Tumors

Eligibility Criteria: * Patient age \>= 18 years * performance status of 0-3 * Vertebral and/or paraspinal metastases, with or without prior surgery and/or fractionated radiotherapy * Benign extradural spine tumors such as chordomas, meningiomas, schwannomas, neurofibromas, paragangliomas, and arteriovenous malformations (AVMs). * Established histologic diagnosis of a benign or malignant tumor of the spine. * Arteriovenous malformation of the spine identified radiographically (no biopsy) * Well-defined lesion involving no more than 2 adjacent vertebral levels or spinal segment * Minimal spinal canal compromise that is not rapidly progressive. Ideally, the tumor should not be within 5 mm of the spinal cord. * If chemotherapy is planned, ideally it should not have been given within 30 days of starting radiation and should not resume until at least 2 weeks after completing radiation. In addition, it is not recommended to perform SBRT when targeted anti-angiogenesis therapy is planned within 2 months of the procedure. * Signed study-specific consent form Exclusion Criteria: * Lesion involving \> 3 adjacent vertebral levels * Overt spinal instability * Neurologic deficit due to bony fragments/bony compression of neural structures * Prior radiotherapy at the involved level(s) within 3 months of radiosurgery, more than one prior course of radiotherapy at the involved level(s), or more than 45 Gy previous radiation exposure at the involved level(s) * Rapidly progressive spinal cord compromise or neurological deficit * Paralysis, or otherwise compromised motor function due to radiographically confirmed cord compression * Patient unable to undergo an MRI * Pregnant or lactating women, due to potential exposure of the fetus to RT and unknown effects of RT on lactating females * Patients with psychiatric or addictive disorder that would preclude obtaining informed consent