Stereotactic ablative radiation therapy for spinal metastases: experience at a single Brazilian institution

Background: This study aims to assess the clinical outcomes of patients with spine metastases who underwent stereotactic ablative radiation therapy (SABR) as part of their treatment. SABR has arisen as a contemporary treatment option for spinal metastasis patients with good prognoses. Materials and methods: Between November 2010 and September 2018, Spinal SABR was performed in patients with metastatic disease in different settings: radical (SABR only), postoperative (after decompression and/or fixation surgery), and reir-radiation. Local control (LC), pain control, overall survival (OS) and toxicities were reported. Results: Eighty-five patients (corresponding to 96 treatments) with spine metastases were included. The median age was 59 years (range, 23-91). In most SABR (82.3%, n = 79) was performed as the first local spine treatment, while in 12 settings (12.5%), fixation and/or decompression surgery was performed prior to SABR. Two-year overall survival rate was 74.1%, and median survival was 19 months.The LC rate at 2 years was 72.3%. With regard to pain control, among 67 patients presenting with pain before SABR, 83.3% had a complete response, 12.1% had a partial response, and 4.6% had progression. Vertebral compression fractures occurred in 10 patients (11.7%), of which 5 cases occurred in the reirradiation setting. Radiculopathy and myelopathy were not observed. No grade III or IV toxicities were seen. Conclusion:This is the first study presenting a Brazilian experience with spinal SABR, and the results confirm its feasibility and safety. SABR was shown to produce good local and pain control rates with low rates of adverse events.