Current concepts in transarterial chemoembolization of hepatocellular carcinoma.

Transarterial chemoembolization (TACE) has the potential to improve survival in patients with intermediate stage hepatocellular carcinoma (HCC). Careful selection of patients is mandatory to gain survival benefit and safe quality of life. Basic principles of TACE in HCC include selective treatment via intrahepatic and extrahepatic arteries, proper management of side effects and continuation of treatment guided by imaging. After conventional TACE, based on delivery of cytotoxic drugs emulsified in iodized oil and embolization of various types of particles, has been used for more than 20 years, the new concept of drug-eluting microspheres has been introduced. This technology effectively combines enhanced local drug delivery and ischemic embolization effects. Clinical studies showed intensified local necroses and reduced systemic toxic side effects compared to conventional TACE. Embolization of HCC with sub-100 μm particles penetrating deeply into the tumor vascular bed is another promising new option. Very effective devascularization of HCC nodules has been shown after 40 μm bland embolizations, however, potential risks like passage of particles into hepatic veins and systemic circulation have to be considered. Today the indication for TACE in intermediate stage HCC patients is widely accepted; however, there is no clear methodical standard so far. Further studies are necessary to define how to adapt various available methods to individual HCC and patients characteristics.