Percutaneous ablation of liver tumors

Abstract

Primary and secondary liver tumors are very common. In developed countries, hepatocellular carcinoma (HCC) is the third cause of cancer death with a poor survival rate in advanced cases. If a curative treatment can be applied at an early stage the overall survival is markedly improved. Many patients (80–90%) cannot undergo radical surgery due to general health status, previous abdominal surgery, diffuse lesion with insufficient liver remnant after their complete removal, or anatomical unfavorable locations. For these reasons, percutaneous treatments have become auspicious treatments for liver tumors due to minimal invasiveness, effectiveness, repeatability, and low costs. Different modalities are accepted for percutaneous ablation procedures and can be divided into thermal and non-thermal ablation techniques. Thermal techniques are monopolar and multipolar radiofrequency ablation (RFA), microwave ablation (MWA), laser ablation (LSA), cryoablation (CRA), and high-intensity focused ultrasound (HIFU). Non-thermal techniques are percutaneous ethanol injection (PEI) and irreversible electroporation. Combinations of the different techniques are possible. These ablative techniques provide necrotization of tumor tissue in different ways, such as thermal coagulation, rapid freezing, or chemical cell dehydration. The procedural planning is divided into three different phases (1) preprocedural planning, (2) intraprocedural targeting, monitoring, and modification, (3) postprocedural assessment. Imaging techniques are of crucial importance in all these phases. Complication after percutaneous techniques occurs in 3–7% of patients.