Innovative therapy for hepatocellular carcinoma: three-dimensional high-dose photon radiotherapy

The development of three-dimensional conformal radiotherapy (3DCRT) has enabled high dose radiation to be directed to tumour with a frank sparing of the non-tumour surrounding liver parenchyma without restriction due to tumour topography and size, presence of peritumourous satellite nodules or associated segmental portal vein thrombosis. 3DCRT can be safely delivered alone or concomitantly with transarterial chemoembolization (TACE), giving very encouraging results. Efficacy is strongly related to a smaller tumor size and higher dose of radiation while toxicity closely correlates to the pre-radiotherapy liver functions and the dose delivered to the uninvolved liver. These data has led to integrate 3DCRT in the multimodal treatment of HCC as a possible curative-intent option as well as surgical resection or percutaneous procedures although phase-III controlled studies are warranted to clarify this point. This may represent a promising approach in patients who are inoperable or for whom other ablation therapies are not feasible. The next steps will be the optimization of delivery modes of this type of photon therapy, taking account that other radiation modalities such as proton beam therapy for instance might be shown as of great interest within the next few years.