Comparison of tissue pressure and ablation time between the LeVeen and cool-tip needle methods

BACKGROUND: Radio frequency ablation (RFA) has been accepted clinically as a useful local treatment for hepatocellular carcinoma (HCC). However, intrahepatic recurrence after RFA has been reported which might be attributable to increase in intra-tumor pressure during RFA. To reduce the pressure and ablation time, we developed a novel method of RFA, a multi-step method in which a LeVeen needle, an expansion-type electrode, is incrementally and stepwise expanded. We compared the maximal pressure during ablation and the total ablation time among the multi-step method, single-step method (a standard single-step full expansion with a LeVeen needle), and the method with a cool-tip electrode. Finally, we performed a preliminary comparison of the ablation times for these methods in HCC cases. RESULTS: A block of pig liver sealed in a rigid plastic case was used as a model of an HCC tumor with a capsule. The multi-step method with the LeVeen electrode resulted in the lowest pressure as compared with the single-step or cool-tip methods. There was no significant difference in the ablation time between the multi-step and cool-tip ablation methods, although the single-step methods had longer ablation times than the other ablation procedures. In HCC cases, the multi-step method had a significantly shorter ablation time than the single-step or cool-tip methods. CONCLUSION: We demonstrated that the multi-step method was useful to reduce the ablation time and to suppress the increase in pressure. The multi-step method using a LeVeen needle may be a clinically applicable procedure for RFA

Estimation of Indication for Living Donor Liver Transplantation in Patients with HCV and/or HBV Infection

We evaluated 78 patients with chronic viral hepatitis for liver transplantation. 51 patients met our original criteria for liver transplantation,and 35 patients of them suffered from hepatocellular carcinoma (HCC). Patients with HCC were significantly older and showed higher prothrombin activity than those without HCC. Eighteen of 35 patients with HCC did not meet the Milan criteria, and they showed lower levels of total bilirubin, Child-Pugh score, and MELD score than those who met the criteria. Theses results indicate that acceptability for transplantation should be evaluated soon after the patients have become candidates for liver transplantation. In Japan, decompensated liver cirrhosis is a necessary condition for the application of public health insurance against liver transplantation and,in cases with HCC,it is necessary to meet the Milan criteria.Application to liver transplantation should also be considered based on HCC stage such as the UNOS scoring system