Surgical resection versus thermal ablation: comparison of sequential options after successful TACE downstaging therapy for unresectable hepatocellular carcinoma.

Background: Transarterial chemoembolization (TACE) is an effective and safe downstaging therapy for hepatocellular carcinoma (HCC). However, the selection of sequential therapeutic modalities is still controversial.

Objectives: This study compared the effectiveness and safety of surgical resection (SR) and thermal ablation (TA) after patients with HCC underwent TACE downstaging therapy.

Design: A retrospective, multi-institutional study.

Methods: From June 2008 to October 2022, a total of 4782 consecutive patients with HCC beyond the initial Milan criteria underwent TACE at 12 hospitals. Among them, 609 patients who received successful downstaging therapy were retrospectively reviewed. Among them, 209 patients underwent an SR, and 390 patients received TA after TACE. The propensity score matching (PSM) method was applied to reduce selection bias between groups. Cumulative overall survival (OS) and progression-free survival (PFS) were compared using the Kaplan-Meier method with the log-rank test.

Results: After PSM 1:1 (n = 185 in both groups), the cumulative 1-, 3-, 5-, and 10-year OS rates were 98.8%, 89.3%, 82.9%, and 64.4%, respectively, in the SR group and 99.5%, 88.4%, 75.3%, and 53.9%, respectively, in the TA group; these two groups were not significantly different (HR: 1.22; 95% CI: 0.78-1.89; p = 0.381). The cumulative 1-, 3-, 5-, and 10-year PFS rates were 88.5%, 69.2%, 58.8%, and 32.2%, respectively, in the SR group and 90.6%, 71.4%, 53.1%, and 32.0%, respectively, in the TA group, revealing no significant difference between the two groups (HR: 0.97; 95% CI: 0.71-1.32; p = 0.855).

Conclusion: For HCC patients beyond the Milan criteria who received TACE downstaging therapy, TA might be acceptable as an alternative to SR in the first-line sequential treatment scheme.