Carbon Ion Radiotherapy for Hepatocellular Carcinoma

The objective of this paper is to present a summary explanation of the clinical study on carbon ion radiotherapy for hepatocellular carcinoma (HCC) conducted from April 1995 to August 2005 at the Research Center for Charged Particle Therapy, National Institute of Radiation Sciences, Japan. A total of 193 patients with HCC were enrolled in the clinical trials with carbon ion beams. In the first and second phase I/II clinical trials, dose escalation experiments were carried out in incremental steps of 10%, resulting in the confirmation of both the safety and the effectiveness in short-course regimens of 12, 8 and 4 fractions. Based on the results, a phase II clinical study with fixed fractionation, that is, 52.8 GyE/4 fractions, was performed, where 47 patients were treated with low toxicity, attaining a high local control rate of 95% at 5 years. The last clinical study was conducted from April 2003 to August 2005 with an even more hypofractionated regime of 2 fractions/2 days, in which 36 patients were safely treated within a dose escalation range from 32.0 GyE to 38.8 GyE. The 2-fraction therapy protocol is continuing under the license of Highly Advanced Medical Technology. There have been no therapy-related deaths and no severe adverse events until now.We can conclude that because of the low toxicity and high local control rate, carbon ion radiotherapy has a promising potential as a new, radical, and minimally invasive therapeutic option for HCC.NIRS-ETOILE Joint Symposium 2009 on Carbon Ion Radiotherap