Current role of proton beam therapy in patients with hepatocellular carcinoma

Abstract

Hepatocellular carcinoma (HCC) is the most common primary liver cancer, the sixth most common cancer, and the fourth leading cause of cancer related deaths worldwide. There are curative local treatment options for HCC, including liver transplantation, surgical resection, and radiofrequency ablation, all of which are applicable for a few patients. For advanced HCC, systemic treatments, such as target agents or immunotherapies, are recommended, however, with unsatisfactory efficacy. Therefore, radiation therapy (RT) has been used as an alternative or combination therapy. With the advances of RT technique in image guidance and accurate beam delivery, its applications have increased for the management of HCC. Proton beam therapy (PBT) is a highly advanced RT technique. Since proton beams have unique physical properties with a finite range in the distal direction, PBT has the potential to escalate the radiation dose without a significant increase in the risk of complications compared with X-ray therapy in the treatment of HCC. Various studies have reported favorable oncological outcomes and toxicity risks of PBT for HCC patients. In this review, we discuss the physical and biological properties, technical issues, current clinical data, and future perspectives on PBT for the treatment of HCC patients.

Keywords

• hepatocellular carcinoma; proton beam therapy; radiation therapy