Radiofrequency Ablation and Cryoablation in Treating Painful Bone Metastasis: A Comprehensive Systematic Review and Separate Single-Arm Meta-analysis.

Background and Aim: Bone metastases cause pain and disability in advanced prostate, breast, and lung cancers. Traditional treatments may not work for all patients. Minimally invasive procedures such as cryoablation (CA) and radiofrequency ablation (RFA) have emerged as good options. This review aims to evaluate and summarize the effectiveness and safety of CA and RFA separately in managing painful bone metastases. Methods: We performed a comprehensive search of Ovid Medline, Google Scholar, Web of Science, CENTRAL, and ClinicalTrials.gov covering studies published between January 2000 and January 2025. The search included English-language cohorts. or randomized trials of adults (≥18 years) with bone metastases treated using RFA or CA. Outcomes such as pain levels, tumor recurrence, and adverse events were collected from each study. To assess the quality and reliability of the studies, we used the Cochrane Risk of Bias 2 (RoB 2) tool for randomized trials and the ROBINS-I tool for nonrandomized studies. We performed separate single-arm meta-analyses for RFA and for CA and integrated findings from the small number of direct comparative studies using a narrative synthesis.We performed separate single-arm meta-analyses for RFA and for CA and integrated findings from the small number of direct comparative cohort studies using a narrative synthesis. Results: A total of 30 studies involving 1121 patients were included in the qualitative synthesis, and 24 were included in the meta-analysis. Separate single-arm meta-analyses revealed that both radiofrequency ablation (RFA) and cryoablation (CA) significantly reduced pain at all follow-up timepoints. RFA had the greatest pain reduction at 6 months (SMD: -3.50; 95% CI: -4.42, -2.27), whereas CA had a greater effect at 24 hours (SMD: -2.43; 95% CI: -3.84, -1.02) but ,a smaller effect at 6 months (SMD: -2.14; 95% CI: -3.43, -0.85). Both were safe, with mostly mild adverse events. The reported tumor control outcomes have been inconsistent, limiting conclusions in this area. Conclusion: On separate analyses, CA appeared to produce larger short-term effect sizes (greater early pain reduction) while RFA had larger medium/long-term effect sizes in the available studies. Because direct comparative data are sparse and heterogeneous, these observations do not establish superiority of one modality over the other. Both techniques demonstrated favorable safety profiles across included studies. Ablation combined with external beam radiation therapy (EBRT) was superior to either modality alone. Standardized measures and more comparative studies are needed to guide treatment.