Background and aims:
While radiofrequency ablation (RFA) is the current standard local ablative modality for early stage hepatocellular carcinoma (HCC), more recently microwave ablation (MWA) is being increasingly used because of its potential advantages. However, it is unclear as to whether MWA achieves similar efficacy and safety outcomes. We conducted a systematic review and meta-analysis to evaluate the efficacy and safety of MWA versus RFA in the treatment of HCC.
A systematic search of MEDLINE, EMBASE, and Cochrane CENTRAL from inception until October 2015 was conducted. Only randomised controlled trials (RCT’s) investigating the efficacy and safety of RFA versus MWA as treatment of (HCC) were included with no language and time limitations. The selection of trials, data extraction and the assessment of bias were performed by two independent review authors. Risk ratio (RR) with 95% confidence intervals (CI) was calculated as the relevant effect measure to analyse complete ablation, local recurrence rates, and safety.
Three studies involving 225 patients and 264 nodules (≤ 5cm) were identified. No difference found in complete ablation rates between MWA and RFA; the pooled RR (95%CI) was 0.99 (0.93-1.05) with no significant inter-study heterogeneity observed (I2=0%). There was no difference in local recurrence and major complications rates between MWA and RFA; the pooled RR was 0.94 (0.30-2.87) and 0.95 (0.07-13.05) with significant inter-study heterogeneity present (I2=63%) and (I2=74%) respectively. Similar results were found on sensitivity analysis evaluating the two studies of higher quality.
This systematic review and meta-analysis demonstrates that the efficacy and safety of MWA appears similar to that of RFA for the treatment of HCC with no significant differences observed in rates of complete ablation, local recurrence and major complications. However, given the low quality of evidence overall and significant inter-study heterogeneity further data is needed via high quality RCT’s.