Results of the first prospective study of carbon ion radiotherapy for hepatocellular carcinoma with liver cirrhosis

Purpose To evaluate the toxicity and antitumor effect of carbon ion radiotherapy for hepatocellular carcinoma within a Phase I-II trial. Methods and materials Between June 1995 and February 1997, 24 patients with histopathologically proven hepatocellular carcinoma were treated to 15 fractions within 5 weeks in a step-wise dose-escalation study. The disease stage was Stage II in 10, IIIA in 6, and IVA in 8 patients. The Common Toxicity Criteria, Radiation Therapy Oncology Group/European Organization for the Research and Treatment of Cancer criteria, and Child-Pugh score were used to evaluate toxicity. The antitumor effect was evaluated by the tumor response, cumulative local control, and survival rates. Results During a median follow-up of 71 months (range, 63–83 months), no severe adverse effects and no treatment-related deaths occurred. The Child-Pugh score did not increase by >2 points after the start of therapy. In 78% and 75% of all patients, the score did not increase by >1 point in the early and late phase, respectively. The overall tumor response rate was 71%. The local control and overall survival rate was 92% and 92%, 81% and 50%, and 81% and 25% at 1, 3, and 5 years, respectively. Conclusion Carbon ion radiotherapy appears safe and effective for patients with hepatocellular carcinoma. Additional clinical studies using a larger subject group are required to confirm the therapeutic efficacy.