Comparative study of the effects of percutaneous ethanol injection and radiofrequency ablation in cases treated with a straight or expandable electrode

Abstract

Radiofrequency ablation (RFA) has become mainstream among non-surgical treatment modalities in clinical settings for the treatment of hepatocellular carcinoma. We have previously described the novel combination therapy of percutaneous ethanol injection and RFA (PEI-RFA) and reported that this combination therapy was more effective than RFA alone in terms of the induced volume of coagulated necrosis and the energy requirement for the treatment. RFA instruments are mainly divided into two types according to the electrode used, either the straight or expandable type electrode. Although PEI-RFA can be performed by either of the electrodes, there may be some important differences in PEI-RFA according to the type of electrode used. In the present study, the effect of using the straight or expandable electrode in PEI-RFA was evaluated by analyzing the ablation time, volume of coagulated necrosis, the energy requirement for ablation and the amount of injected ethanol into HCC. The comparative study showed that ablation time, total energy requirement and per unit volume of energy requirement for whole and marginal coagulated necrosis were significantly smaller in the group treated with the expandable electrode (E group) than those in the group treated with the straight electrode (S group). The volume of coagulated necrosis was similar between these groups. In group E, the amount of injected ethanol showed a positive correlation with the volume of coagulated necrosis and the size of the tumors. These results suggest that prior injection of ethanol works mainly by shortening the time and energy requirement for ablation in the time-lag PEI-RFA using the expandable electrode. Thus, prior injection of ethanol before RFA may make RFA treatment less invasive in the time-lag PEI-RFA using the expandable electrode as previously shown HCC cases treated with straight electrode.

Effects of radiofrequency ablation versus other ablating techniques on hepatocellular carcinomas: a systematic review and meta-analysis

“…A trend suggests that PEI-RFA may be utilized in 3.1–5-cm tumors. Kazutaka et al [ 38 ] reported larger areas of coagulated necrosis in the PEI-RFA group (34 ± 29.3 cm 3 ) than in the RFA group (6.5 ± 3.6 cm 3 ; P < 0.0001). The amount of ethanol injected into the tumor was significantly and positively correlated with the volume of coagulated necrosis, but not with the energy requirement.…”

Role of Interventional Radiology in Management of Hepatocellular Carcinoma: Systematic Review

“…LSA was associated with decreased CTA rates (OR 0.32, 95% CI 0.13-0.81) and overall survival (hazard ratio 1.47, 95% CI 1.01-2.15), as well as less comorbidities. Kazutaka and colleagues [29]. The PEI-RFA group had bigger regions of coagulated necrosis (34 29.3 cm3) than the RFA group (6.5 3.6 cm3; P 0.0001).…”