Robotic Stereotactic Body Radiotherapy for Spine Metastasis Pain Relief

Abstract

Spinal metastasis may occur in 40–70% of patients with cancer. Symptoms can vary from pain to spinal cord compression (SCC) and can affect their quality of life (QoL). Stereotactic body radiotherapy (SBRT) allows dose escalation of spinal tumor metastases, minimizing doses to organs at risk and improving pain control. The aim of this study is to retrospectively describe our institution’s experience with robotic SBRT (CyberKnife®, Accuray Incorporated, Sunnyvale, CA, USA) for spinal metastases, in terms of feasibility, oncological results, toxicities, and pain relief observed. In total, 25 patients with 43 lesions were assessed, most of them with dorsal metastases (48.8%). The median total dose was 27 Gy (16–35 Gy), the median number of fractions administered was 3 (1–5), and the median dose per fraction was 9 Gy. Pain was evaluated using the visual analogue scale at baseline and at the end of treatment. The statistically significant reduction in pain (p < 0.01) was associated with the total dose of radiotherapy delivered (p < 0.01). Only one patient developed grade 3 dermatitis. Female gender, adenocarcinoma tumors, and lack of previous surgery were associated with better response to SBRT (p < 0.05). Robotic spine SBRT is feasible, well-tolerated, and improves patients’ QoL through a statistically significant reduction in pain, so it should be offered to patients at an early stage in their process.