1. 2019;22;E441-E449Spinal Radiofrequency Ablation Combined with Cement Augmentation for Painful Spinal Vertebral Metastasis: A Single-Center Prospective Study
   Prospective Evaluation
   Walter Orr, MPH, Daniel Haines, MD, Timothy Sowder, MD, Daniel Jacobs, DO, and Dawood Sayed, MD.

BACKGROUND: The spine is the most common site of skeletal metastatic disease. Vertebral body metastases (VBM) can cause crippling pain, fractures, and spinal cord compression. Radiofrequency ablation (RFA) is a minimally invasive technique that has proven to be a safe method of targeted tissue destruction. Studies have shown that RFA combined with cement vertebral augmentation is safe and effective and has been associated with significant improvements in pain and quality of life.

OBJECTIVES: The purpose of this study was continued evaluation of the safety and efficacy of this technique.

STUDY DESIGN: Prospective cohort.

SETTING: A single academic medical center.

METHODS: Patients undergoing RFA with cement vertebral augmentation for a painful thoracic or lumbar VBM were eligible for inclusion. Additional inclusion criteria included pain concordant with a metastatic lesion on cross-sectional imaging, aged 18 years or older, and considered candidates for spinal tumor ablation by the operating physician. Patients with vertebral metastatic disease in the cervical spine or patients with spinal cord compression from posterior tumor extension were excluded. Ablation within each VBM was performed using a bipolar radiofrequency probe with an extensible electrode and available articulation, permitting vertebral body navigation percutaneously. Patients were evaluated at baseline, 3 days, one week, one month, and 3 months using the Numeric Rating Scale (NRS-11) and Functional Assessment of Cancer Therapy-General 7 (FACT-G7) to assess pain and quality-of-life, respectively. A one-sample t test was performed, and 95% confidence intervals were calculated to assess changes in average NRS-11 and FACT-G7 scores.

RESULTS: A total of 30 patients met inclusion criteria and underwent RFA of one or more VBM. Patients with 13 different primary cancers types underwent treatment. Patients received RFA to either one (n = 26; 87%) or 2 vertebral body levels (n = 4; 13%). Of the 34 levels, 13 were thoracic vertebra (38%) and 21 were lumbar vertebra (62%). Average NRS-11 scores decreased from a baseline of 5.77 to 4.65 (3 days; P = 0.16), 3.33 (one week; P < 0.01), 2.64 (one month; P < 0.01), and 2.61 (3 months; P < 0.01). FACT-G7 increased from a baseline average of 13.0 to 14.7 (3 days; P = 0.13), 14.69 (one week; P = 0.15), 14.04 (one month; P = 0.35), and 15.11 (3 months; P = 0.07). No major adverse events were reported.

LIMITATIONS: A heterogeneous patient population, small sample size, and potential confounders of concurrent variable adjuvant therapies were limitations. Additionally, most patients received both cement augmentation and targeted RFA, making it difficult to distinguish independent analgesic benefits of the therapies.

CONCLUSIONS: This study demonstrates that minimally invasive targeted RFA with cement augmentation of spinal metastatic lesions is an effective treatment for patients with VBM.

KEY WORDS: Cancer, cancer pain, spinal metastasis, radiofrequency ablation, tumor ablation, cement augmentation