Percutaneous Radiofrequency Ablation in the Treatment of Primary Liver Cancers

The development of image-guided percutaneous techniques for local tumor ablation has been one of the major advances in the treatment of primary liver malignancies. Among these methods, radiofrequency (RF) ablation is one of the most established primary ablative modalities at most institutions. In the setting of patients of early stage hepatocellular carcinoma (HCC) – according to the Barcelona Clinic Liver Cancer (BCLC) staging system – and those with a single nodule ≤3cm of intrahepatic cholangiocarcinoma (ICC), image-guided tumor ablation is recommended when surgical resection is not feasible. The goal of RF ablation is to induce thermal injury to the tissue through electromagnetic energy deposition. One or multiple electrodes have to be inserted directly into the tumor to deliver RF energy current. Electrodes are coupled with RF generators and can be monopolar or bipolar, and they can have different designs (multitined expandable, internally cooled, and perfused). Targeting of the lesion can be performed with US, CT, or MR imaging guidance. The guidance system is chosen largely based on operator preference and local availability of dedicated equipment such as fluoro-CT, MR systems, or robotic devices with electromagnetic or infrared navigation.