1. 2018;21;E467-E476Efficacy Assessment of Radiofrequency Ablation as a Palliative Pain Treatment in Patients with Painful Metastatic Spinal Lesions: A Systematic Review
   Systematic Review
   Katharina Rosian, MSc, Katharina Hawlik, MD, and Brigitte Piso, MD.

BACKGROUND: Metastatic spinal lesions are difficult-to-treat entities that are most commonly associated with pain and severely reduced health-related quality of life (HRQoL). Within the last 5 to 10 years, radiofrequency ablation (RFA) has emerged as an option in the palliative treatment of vertebral metastases.

OBJECTIVES: Our review aims to evaluate the clinical effectiveness and safety of RFA, mostly in combination with vertebroplasty, in patients with painful vertebral metastases.

STUDY DESIGN: The design of this study is a systematic review.

METHODS: We conducted a systematic literature search and a manual search of 5 databases in December 2016. The review applied a methodological framework based on the HTA Core Model®. Data on each selected outcome category were synthesized according to the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) scheme. Risk of bias was assessed using the Institute of Health Economics (IHE) Risk of Bias checklist for case series.

RESULTS: We identified 299 citations. After applying the inclusion criteria, a total of 9 studies (4 prospective and 5 retrospective studies) were determined to be eligible. These studies included a total of 583 patients with vertebral metastases who were treated with RFA and, in most cases, received an additional vertebroplasty treatment (n = 437). The studies were categorized as having a moderate to high risk of bias. The strength of evidence was found to be “very low” for safety outcomes and could not be assessed for efficacy outcomes. Current evidence suggests that RFA leads to significant pain reduction. Furthermore, no major complications occurred when using RFA.

LIMITATIONS: A major concern is the low number of included patients and heterogeneity of study characteristics in most of the studies. The low number of patients also impeded comparison of the effectiveness of RFA alone to RFA in combination with vertebroplasty.

CONCLUSION: According to the available evidence, RFA may be safe and effective, especially for patients with painful vertebral metastases who show contraindications or unresponsiveness to conventional therapies (e.g., radiation) or for those who are at risk of tumor progression.

KEY WORDS: Radiofrequency ablation, vertebral metastases, metastatic spinal lesions, pain, clinical effectiveness, safety, palliative pain treatment