Hepatocellular carcinoma with portal vein tumor thrombosis: Improved treatment outcomes with external beam radiation therapy.

The treatment of advanced hepatocellular carcinoma (HCC) associated with portal vein tumor thrombosis (PVTT) is very challenging because of HCC's grave prognosis. Despite many efforts to improve the treatment results, patient survival has been limited to several months. In this situation, radiotherapy has been considered as an alternative treatment modality because of the growth of knowledge about the radiotolerance of normal tissue and the advances of radiotherapy techniques such as three dimensional conformal radiotherapy, intensity modulated radiotherapy, stereotactic body radiotherapy and proton therapy. More restoration of the liver function and longer survival of the patients can be achieved by the better response after radiotherapy. However, considering the high risk of intrahepatic advanced tumor or extrahepatic dissemination by PVTT at disease presentation, a combination of radiation therapy and systemic agents will be desirable. Therefore, performing prospective randomized clinical trials is important to assess the benefits of radiotherapy and to develop combination treatment strategies.