Tips for Preparing and Practicing Thermal Ablation Therapy of Hepatocellular Carcinoma

SIMPLE SUMMARY: Thermal ablation, including radiofrequency ablation (RFA) and microwave ablation (MWA), for hepatocellular carcinomas (HCCs) is accepted as a curative treatment option in many HCC treatment guidelines because of the better clinical outcomes performed in a more minimally invasive manner. Essential management tips to successful ablation therapy can be organized into five categories: understanding the principles of ablation therapies and the characteristics of ablation devices, assessing the benefits and risks of ablation, practicing ultrasound-guided needle tip control and visualization, taking advantage of imaging guidance techniques, and evaluating therapeutic response to ensure adequate ablation. We herein provide an overview of the basic principles and characteristics of tissue heating, highlight the safety management of ablation therapy, and provide the technical skills of sophisticated planning and image guidance technologies to improve short- and long-term outcome of HCC patients. These essentials will contribute to the expansion of thermal ablation applications in clinical settings. ABSTRACT: Thermal ablation therapy, including radiofrequency ablation (RFA) and microwave ablation (MWA), is considered the optimal locoregional treatment for unresectable early-stage hepatocellular carcinomas (HCCs). Percutaneous image-guided ablation is a minimally invasive treatment that is being increasingly performed because it achieves good clinical outcomes with a lower risk of complications. However, the physics and principles of RFA and MWA markedly differ. Although percutaneous thermal ablation under image guidance may be challenging in HCC cases with limited access or a risk of thermal injury, a number of ablative techniques, each of which may be advantageous and disadvantageous for individual cases, are available. Furthermore, even when a HCC is eligible for ablation based on tumor selection and technical factors, additional patient factors may have an impact on whether it is the appropriate treatment choice. Therefore, a basic understanding of the advantages and limitations of each ablation device and imaging guidance technique, respectively, is important. We herein provide an overview of the basic principles of tissue heating in thermal ablation, clinical and laboratory parameters for ablation therapy, preprocedural management, imaging assessments of responses, and early adverse events. We also discuss associated challenges and how they may be overcome using optimized imaging techniques.