Study of Combined Decompressive Spine Radiosurgery and Pembrolizumab

Inclusion Criteria : * Pathologic diagnosis of cancer, confirmed by review of pathology report. * Epidural disease seen on MRI at 1 vertebral level or 2 contiguous vertebral level. * Synchronous and metachronous sites of disease allowed. * Patient with expected life span of ≥ 3 months. * Deemed eligible for stereotactic body radiation therapy and pembrolizumab after multi-disciplinary review. The multi-disciplinary review will be conducted virtually via our Spinal Oncology Group (SPOG) Wake Forest e-mail listserv. Members of the distribution list include neurosurgeons, orthopedic surgeons, interventional radiologists, radiologists, and radiation oncologists. This group meets monthly via Webex and in the interim, cases are routinely reviewed using encrypted emails via the listserv. Because we will not be able to wait for a month meeting to enroll patients on study, we anticipate needing to review these patients via the listserv. The electronic review will serve as documentation of multi-disciplinary review. * Patients currently being treated with pembrolizumab or anticipated to receive at least one dose of pembrolizumab within six weeks after finishing stereotactic body radiation therapy. * Patients who have received prior immunotherapy are allowed. * Age equal or greater than 18. * Ability to understand and the willingness to sign an IRB-approved informed consent document (either directly or via a legally authorized representative). Exclusion Criteria: * Prior radiation th…