Efficacy and cost-effectiveness analysis of external beam and stereotactic body radiation therapy in the treatment of spine metastases: a matched-pair analysis

摘要

OBJECT: The objective of this study was to compare the palliative efficacy and cost effectiveness of external beam radiation therapy (EBRT) to stereotactic body radiation therapy (SBRT) as primary treatment for bone metastatic disease of the spinal column. METHODS: Forty-four patients were matched based on age, primary tumor site, year of treatment, and location of metastasis. Outcomes of interest were pain relief, cost-effectiveness, toxicities, and need for further intervention. Pain relief was rated as excellent, good, fair, or poor, using a radiosurgical pain scale to combine visual analog scale and verbal descriptor ordinal scale scores. Medicare fee schedules were used to compute the charges for both the technical and professional components of care. Patients in the EBRT group were treated using a linear accelerator while patients in the SBRT group were treated with the CyberKnife robotic radiosurgery system. Patients received regular follow-up evaluations by a radiation oncologist and neurosurgeon. RESULTS: Forty-four patients (22 pairs) were analyzed. At a follow-up of 1 month, there was no statistically significant difference in pain between the 2 groups (p = 0.11). Patients who underwent SBRT had the highest total gross charge; depending on technique, EBRT treatments ranged from 29% to 71% of the SBRT charge. Patients treated using EBRT had more acute toxicities, and more of these patients underwent further intervention at the treated spinal level. There were no late complications attributed to either treatment modality. CONCLUSIONS: External beam radiation therapy remains an efficacious and cost-effective method of palliation of spine metastases. In this study, patients treated with EBRT had more acute toxicities and were more likely to require additional interventions at the treated sites. Stereotactic body radiation therapy, although more costly, resulted in comparable rates of pain relief and late treatment-related toxicity, and continues to show promise as an emerging modality for selected patients with spine metastases.