Preoperative Stereotactic Radiotherapy for Spinal Metastases: Study Protocol for a Prospective Exploratory Interventional Trial

BACKGROUND AND OBJECTIVES: Spinal metastases frequently require surgical stabilization and/or decompression followed by postoperative radiotherapy (RT). Preoperative stereotactic body radiotherapy (SBRT) may reduce postoperative complications and improve local tumor control. The primary objective of this exploratory trial is to evaluate safety and preliminary efficacy of preoperative SBRT in patients with spinal metastases. METHODS: The Preoperative Stereotactic Radiotherapy for Spinal Metastases study is a single-center, prospective, exploratory, interventional trial that will enroll 20 patients scheduled for surgical treatment of spinal metastases at University Medical Center Göttingen. Patients will receive SBRT (1-3 fractions) performed 1 to 3 days before surgery. The primary endpoint is local tumor control at 3 months after surgery. Secondary endpoints include pain control, wound healing disturbances, quality of life, neurological function, and instrumentation failure. EXPECTED OUTCOMES: The study is expected to provide first prospective data on the feasibility and safety of integrating preoperative SBRT into the treatment sequence for spinal metastases. It will also generate early evidence on local tumor control, perioperative morbidity, patient-reported outcomes, and instrumentation-related outcomes. DISCUSSION: Preoperative Stereotactic Radiotherapy for Spinal Metastases evaluates a novel treatment sequence intended to address limitations of postoperative RT, including delayed treatment initiation and implant-related planning challenges. The rationale is supported by preoperative SBRT approaches for brain metastases, where treatment of the intact lesion before resection has been investigated to improve target definition and avoid irradiation of postoperative cavities. The study is intended to generate initial feasibility, safety, and preliminary efficacy data that may inform the design of a subsequent randomized trial comparing preoperative with postoperative RT.