Recurrence patterns and survival outcomes after irreversible electroporation for hepatocellular carcinoma: a 6-year multicenter experience.

Abstract

Objectives: Irreversible electroporation (IRE) is a relatively recent non-thermal ablation technique for hepatocellular carcinoma (HCC) in high-risk anatomical locations, but post-procedural recurrence limits long-term survival. This study aimed to investigate the risk factors, patterns, and outcomes of post-IRE recurrence.

Materials and methods: This study retrospectively analyzed 180 patients with solitary HCC (≤ 5 cm) who underwent IRE at five centers. Recurrence was categorized as local tumor progression (LTP), intrahepatic distant recurrence (IDR), aggressive intrasegmental recurrence (AIR), and extrahepatic distant recurrence (EDR). Competing-risk regression models and dynamic risk curves were utilized to assess risk factors and temporal trends.

Results: Over a mean follow-up of 40.9 ± 12.6 months, 50.6% of patients developed recurrence. IDR was the predominant pattern (41.7%), followed by LTP (10.0%), EDR (8.3%), and AIR (1.7%). Multivariate analysis identified cirrhosis and tumor size as predictors of LTP; recurrent HCC and cirrhosis as predictors of IDR; and the male sex, cirrhosis, and tumor size as predictors of EDR (all p < 0.05). Only EDR was an independent risk factor for worse overall survival (p < 0.001). Recurrence risk demonstrated a bimodal pattern, with peaks at 21 and 33 months.

Conclusion: IDR is the dominant post-IRE recurrence pattern, but only EDR predicts survival. The identified risk factors and bimodal recurrence peaks contribute to guiding stratified therapeutic strategies for HCC in high-risk locations.

Key points: Question Current knowledge of post-ablation recurrence patterns for hepatocellular carcinoma is primarily derived from thermal ablation, lacking data for non-thermal irreversible electroporation. Findings Intrahepatic distant recurrence was the most common recurrence pattern, while only extrahepatic distant recurrence predicted worse survival. Clinical relevance Irreversible electroporation provided excellent local control for high-risk hepatocellular carcinoma but struggled with recurrence. While extrahepatic distant recurrence predicted reduced survival, local or intrahepatic recurrences yielded favorable outcomes with salvage therapy.