Role of trans-arterial radiation therapy (Radio embolization) in management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) represents one of the most common forms of cancer with more than one million new cases estimated annually worldwide. It is the most common primary malignancy of the liver. It is the sixth most common malignancy worldwide and the third most common cause of cancer-related mortality (Bosch et al., 2004). The incidence of HCC is becoming more frequent due to an increase in the hepatitis C infection. Treatment options are surgical resection for localized lesions or alternative measures for advanced cases. (Townsend, 2004). Over the last two decades, the treatment of HCC has undergone considerable changes with the development of new locoregional and systemic therapies (and a broadening of the indication for liver surgery and liver transplantation) (Herrero et al., 2009). Many of these improvements have been included in a therapeutic algorithm that derives from a staging system for HCC patients which was endorsed by The American Association for the Study of Liver Diseases (AASLD) and The European Association of Study of Liver Disease (EASL). This algorithm recommends different treatments for each tumor stage, taking into account the tumor burden, the severity of underlying liver cirrhosis, and the performance status of the patient. In early stages, radical therapies, including percutaneous ablation, liver resection, and liver transplantation, are recommended. For intermediate stage, trans-arterial chemo embolization (TACE) is the treatment of choice. For advanced tumors, systemic therapy with the novel tyrosine kinase inhibitor, sorafenib, has become the standard of care. (Bruix and Sherman., 2011). Among the novel therapeutic procedures, yttrium-90 radio embolization (⁹⁰Y-RE) has produced encouraging results across the whole spectrum of HCC, from early to advanced stages.(Hilgard et al., 2010). This treatment has reported a higher percentage of tumor shrinkage, if compared to TACE, for pre-transplant downsizing and it represents a promising therapeutic option in patients with large extent of disease and insufficient residual liver volume who are not immediately eligible for surgery (Sacco et al., 2015). Radio embolization might also be a suitable companion to sorafenib in advanced HCC or it can be used as a potential alternative to this treatment in patients who are not responding or do not tolerate sorafenib (Sacco et al., 2015)