Comparison of efficacy and toxicity of short-course carbon ion radiotherapy for hepatocellular carcinoma depending on their proximity to the porta hepatis

Background and purpose To compare the efficacy and toxicity of short-course carbon ion radiotherapy (C-ion RT) for patients with hepatocellular carcinoma (HCC) in terms of tumor location: adjacent to the porta hepatis or not. Materials and methods The study consisted of 64 patients undergoing C-ion RT of 52.8GyE in four fractions between April 2000 and March 2003. Of these patients, 18 had HCC located within 2cm of the main portal vein (porta hepatis group) and 46 patients had HCC far from the porta hepatis (non-porta hepatis group). We compared local control, survival, and adverse events between the two groups. Results The 5-year overall survival and local control rates were 22.2% and 87.8% in the porta hepatis group and 34.8% and 95.7% in the non-porta hepatis group, respectively. There were no significant differences ( P= 0.252, P =0.306, respectively). Further, there were no significant differences in toxicities. Biliary stricture associated with C-ion RT did not occur. Conclusions Excellent local control was obtained independent of tumor location. The short-course C-ion RT of 52.8GyE in four fractions appears to be an effective and safe treatment modality in the porta hepatis group just as in the non-porta hepatis group.