Supplementary Material for: C-Arm Cone Beam Computed Tomography Guidance for Radiofrequency Ablation in Hepatocellular Carcinoma

<p><b><i>Objective:</i></b> To assess the usefulness of C-arm cone beam computed tomography (CBCT) combined with ultrasound for the treatment of hepatocellular carcinoma (HCC) by radiofrequency ablation (RFA). <b><i>Methods:</i></b> Patients underwent RFA following transcatheter arterial chemoembolization (TACE) or RFA alone under ultrasound or CBCT guidance combined with ultrasound-based techniques. They were divided into 2 groups based on the use (C group) and nonuse (NC group) of CBCT guidance. The technical success of RFA and local tumor progression after the first RFA session were evaluated by dynamic contrast-enhanced imaging methods. Between-group differences were assessed retrospectively. <b><i>Results:</i></b> We enrolled 198 patients with 260 HCC nodules. The complete ablation rates were 63.0 and 89.4% in the NC and C groups, respectively. In log-rank testing, local tumor progression occurred significantly more often in the NC group when RFA was used without TACE, in males when des-gamma-carboxy prothrombin was ≥29 mAU/mL, and when the diameter of a nodule was ≥18 mm. On Cox proportional-hazards regression analysis, the NC group, RFA alone without TACE, and male gender were significant independent variables. <b><i>Conclusion:</i></b> TACE followed by RFA under CBCT and ultrasound guidance improves the reliability of ablation of target HCC nodules, reduces the need for additional treatment sessions, and prevents local tumor progression.</p