Identification of Risk Factors for the Local Recurrence of Hepatocellular Carcinoma Post-radiofrequency Ablation

Background/Aim: Radiofrequency ablation (RFA) is a mainstay curative treatment for unresectable hepatocellular carcinoma (HCC). Despite the success of RFA, however, some patients with HCC continue to experience local recurrence (LR). The aim of the present study was to identify risk factors for LR post-RFA, considering cases of repeated RFA for LR-HCC separately.

Patients and Methods: This study initially included 829 patients who underwent RFA for HCC at our institution between January 2013 and December 2022. From these, 447 patients with single HCC were selected based on the selection criteria, and they were further classified into a new HCC lesion group (n=400, NL group) and repeated RFA for LR-HCC post-first RFA group (n=47, LR group). The two groups were retrospectively analyzed to identify factors related to LR post-RFA.

Results: In the NL and LR groups, the median observation period after treatment was 36.9 months and 33.7 months, respectively. The cumulative LR rates were 5.1%, 11.0%, and 14.2% in the NL group, and 12.8%, 34.2%, and 40.8% in LR group at 1, 3, and 5 years post-RFA, respectively. The Cox proportional hazard test showed that HCC tumors >1.5 cm [hazard ratio (HR)=3.606; p=0.001] and tumor site (adjacent to blood vessels) (HR=1.932; p=0.035) were identified as independent risk factors for LR post-RFA in the NL group, while only TACE prior to RFA was identified in the LR group.

Conclusion: Tumor size and site of HCC were independent risk factors for LR post-RFA. Moreover, repeated RFA for LR-HCC post-first RFA had quite a high rate of LR post-RFA. For these cases, the selection of modalities other than RFA should be considered.