Comparison of local ablative therapies, including radiofrequency ablation, microwave ablation, stereotactic ablative radiotherapy, and particle radiotherapy, for inoperable hepatocellular carcinoma: a systematic review and meta-analysis

Surgical intervention is the first-line treatment in well-selected hepatocellular carcinoma (HCC) patients. However, only a few patients are suitable to receive radical surgery. We conducted a systematic review and meta-analysis to evaluate local control among four local ablative therapies in inoperable HCC patients, including radiofrequency ablation therapy (RFA), microwave ablation therapy (MWA), stereotactic ablative radiotherapy (SABR), and particle radiotherapy. The primary outcome was the local control rate and the secondary were regional and distant progression rates, overall survival rate, and adverse events. We included twenty-six studies from PubMed, EMBASE, and Cochrane Library databases. MWA (p < 0.001) and particle radiotherapy (p < 0.001) showed better performance of local control compared to RFA, while SABR (p = 0.276) showed a non-significant trend. However, SABR (p = 0.002) and particle radiotherapy (p < 0.001) showed better performance than RFA in HCCs of ≥ 30 mm in size. MWA showed a similar result to RFA while SABR and particle radiotherapy showed a lower survival rate in the 2-, 3-, and 4-year overall survival rates. Our results indicate that MWA, SABR and particle radiotherapy were safe and no inferior to RFA in local control rate. Besides, the local control rates of SABR and particle radiotherapy are better than RFA in HCC of ≥ 30 mm in size. As a result, we suggested that MWA, SABR and particle radiotherapy to be effective alternatives to RFA for inoperable HCC. Moreover, the tumor size should be taken into consideration for optimal treatment selection between local ablative therapies.