Purpose and design: Intra-arterial therapies for unresectable hepatocellular carcinoma (HCC) consist of a catheter-based group of treatments where therapeutic and/or embolic agents are intra-arterially directed to target tumors. Here we review these therapies, which may be classified into embolotherapy/chemotherapy-based and radiotherapy-based treatments. Embolotherapy/chemotherapy-based treatments include transcatheter arterial embolization, transarterial chemoembolization, transcatheter arterial chemoeinfusion, and chemoembolization with drug-eluting beads. Radiotherapy-based treatments include radioembolization with yttrium-90 and injection of iodine-131-labeled lipiodol.
Results and conclusion: Interpretation of the results of clinical trials as well as implementation of meta-analyses involving the efficacy of intra-arterial therapies for unresectable HCC has been challenging and difficult to perform. The levels of evidence for treatment recommendations in oncology provide a common framework to understand the current status of intra-arterial therapies for HCC. Here we use an evidence-based approach to critically review and comprehend the current role and future potential of intra-arterial therapies in unresectable HCC.