LAUSR

ObjectivesTo evaluate and compare clinical outcomes of two different radiofrequency ablation (RFA) methods for locally recurred hepatocellular carcinoma (LrHCC) after locoregional treatment.MethodsOur institutional review board approved this study with a waiver of informed consent. A total of 313 patients previously treated with transarterial chemoembolization (TACE) (n = 167) and RFA (n = 146) with a single LrHCC ≤ 3 cm was included from five tertiary referral hospitals. RFA was done for LrHCCs using either viable tumor alone ablation (VTA) method (VTA: n = 61 in the TACE group and n = 127 in the RFA group) or whole tumor ablation (WTA) method which includes both viable tumor and retained iodized oil or previously ablated zone (WTA: n = 106 in the TACE group and n = 19 in the RFA group). Local tumor progression (LTP)-free survival as well as progression-free survival (PFS) were estimated using the Kaplan-Meier method, and prognostic factors were evaluated using the Cox proportional hazards regression model.ResultsIn 167 patients with LrHCC who underwent TACE, the 5-year LTP-free survival after RFA was significantly higher with the VTA method than with the WTA method (26.9% vs. 87.8%; p < 0.001; hazard ratio (HR) = 8.53 [4.16–17.5]). The estimated 5-year PFS after RFA for LrHCC after TACE using the VTA method was 5.7%, which was significantly lower than that with the WTA method (26.4%) (p = 0.014; HR = 1.62 [1.10–2.38]). However, in 146 patients with LrHCC after initial RFA, there were no significant differences in cumulative incidence of LTP (p = 0.514) or PFS (p = 0.905) after RFA between the two ablation methods.ConclusionsFor RFA of LrHCC after TACE, the WTA method including both viable tumor and retained iodized oil could significantly lower LTP and improve PFS than VTA.Key Points• Whole tumor ablation (WTA) could provide significantly better local tumor control for locally recurred HCC (LrHCC) after TACE than viable tumor alone ablation (VTA).• WTA for LrHCC after TACE could also provide significantly better progression-free survival than VTA.• Regarding LrHCC after RFA, VTA would provide a comparable clinical outcome to WTA.