Percutaneous radiofrequency ablation and transcatheter arterial chemoembolization for hypervascular hepatocellular carcinoma: rate and risk factors for local recurrence.

Purpose: To analyze local recurrence-free rates and risk factors for recurrence following percutaneous radiofrequency ablation (RFA) or transcatheter arterial chemoembolization (TACE) for hypervascular hepatocellular carcinoma (HCC).

Methods: One hundred and nine nodules treated by RFA and 173 nodules treated by TACE were included. Hypovascular nodules were excluded from this study. Overall local recurrence-free rates of each treatment group were calculated using the Kaplan-Meier method. The independent risk factors of local recurrence and the hazard ratios were analyzed using Cox's proportional-hazards regression model. Based on the results of multivariate analyses, we classified HCC nodules into four subgroups: central nodules < or =2 cm or >2 cm and peripheral nodules < or =2 cm or >2 cm. The local recurrence-free rates of these subgroups for each treatment were also calculated.

Results: The overall local recurrence-free rate was significantly higher in the RFA group than in the TACE group (p = 0.013). The 24-month local recurrence-free rates in the RFA and TACE groups were 60.0% and 48.9%, respectively. In the RFA group, the only significant risk factor for recurrence was tumor size >2 cm in greatest dimension. In the TACE group, a central location was the only significant risk factor for recurrence. In central nodules that were < or =2 cm, the local recurrence-free rate was significantly higher in the RFA group than in the TACE group (p < 0.001). In the remaining three groups, there was no significant difference in local recurrence-free rate between the two treatment methods.

Conclusion: A tumor diameter of >2 cm was the only independent risk factor for local recurrence in RFA treatment, and a central location was the only independent risk factor in TACE treatment. Central lesions measuring < or =2 cm should be treated by RFA.