Comparisons between radiofrequency ablation and stereotactic body radiotherapy for liver malignancies: Meta-analyses and a systematic review

Introduction: Radiofrequency ablation (RFA) is a standard ablative modality for small liver malignancies. Stereotactic body radiotherapy (SBRT) has emerged although yet suffers a lack of high-level evidence. We performed meta-analyses and a systematic review to integrate the literature and help in clinical decision-making. Methods: Systemic searches were performed of the PubMed, Medline, and EMBASE databases to identify controlled studies comparing RFA and SBRT. Results: Eleven studies involving 2238 patients were included. Among them, eight studies were for treating early hepatocellular carcinomas (HCCs) and three for liver metastases. Including HCCs and liver metastases studies, the pooled two-year local control (LC) rate was higher in the SBRT arm (83.8%, 95% confidence interval [CI]: 77.6–88.4) than that in the RFA arm (71.8%, 95% CI: 61.5–80.2) (p = 0.024). Among studies on liver metastases, the pooled two-year LC rate was higher in the SBRT arm (83.6% vs. 60.0%, p < 0.001). No significant difference was found between arms in HCC studies (SBRT vs. RFA: 84.5 vs. 79.5% p = 0.431). Pooled analysis of overall survival (OS) in HCC studies showed an odds ratio of 1.43 (95% CI: 1.05–1.95, p = 0.023), favoring RFA. Among the two liver metastases studies with comparative survival data, no significant difference was observed. Conclusion: LC was equivalent between RFA and SBRT for HCC and better for SBRT for the treatment of liver metastases. RFA was associated with better OS for HCC, but discrepancy between LC and OS requires further investigation, as they are local modalities having comparable efficacy.