The Efficacy and Therapeutic Outcome of Bipolar Radiofrequency Ablation for the Treatment for Hepatocellular Carcinoma in the Real-World Setting, Compared with Monopolar Radiofrequency Ablation Conducted during the Same Period

Abstract

<b><i>Background:</i></b> Several reports have suggested that the bipolar radiofrequency ablation (RFA) system is useful for the treatment of hepatocellular carcinoma (HCC). We evaluated the efficacy and safety of the bipolar RFA system for HCC treatment in the real-world setting. <b><i>Methods:</i></b> A total of 155 patients with 224 HCC tumors were enrolled. First, we examined the characteristics and outcomes of two RFA systems, monopolar and bipolar. Second, we identified the factors associated with local tumor progression in 72 patients with 104 HCC tumors, who could be followed up for at least 3 months after treatment and had been treated with the bipolar RFA system. <b><i>Results:</i></b> Of the baseline characteristics, tumor size and location were associated with the selection of the bipolar RFA system. A sufficient ablative zone margin (≥5 mm) was obtained by bipolar RFA in 81 of 94 (86.1%). The 1- and 2-year local tumor progression rates were 15.6 and 26.3%, respectively. An alpha-fetoprotein-L3 (AFP-L3) ratio &#x3e;10% (HR: 7.64; 95% CI: 1.7–39.8, <i>p</i> = 0.007) and an insufficient ablative zone margin (&#x3c;5 mm) (HR: 4.53; 95% CI: 1.02–20.3, <i>p</i> = 0.047) were related to local tumor progression in Cox regression analysis. Although severe adverse events were not observed in most cases, severe hepatic infarction occurred in 1 patient. <b><i>Conclusions:</i></b> The bipolar RFA system is safe and effective for HCC treatment. Tumor localization within the liver is an important factor associated with bipolar RFA. Careful follow-up or reconsideration of treatment is necessary for cases with AFP-L3 ratio &#x3e;10% or insufficient ablative zone margin (&#x3c;5 mm), which were associated with local tumor progression.