A preliminary clinical efficacy of heavy ion (¹²C⁶⁺) beam for hepatic malignance

To evaluate the efficacy and safety of heavy ions (¹²C⁶⁺) for hepatic malignance, we introduced unresectable hepatic malignance, including 3 patients with primary hepatic carcinoma and 4 with liver metastases. The patients were scanned for CT images, and delivered to treatment planning system for delineating the gross tumor volume (GTV). And then the physicians designed the treatment plan. After completing and verifying the treatment plan, the patients were treated by radiotherapy in lanzhou heavy ion research facility using carbon ions (400 MeV·u^{-1 12}C⁶⁺). As of September 2013 within 3 to 16 months, there were no patients lost to follow-up. After 3-month treatment, including PR 4 cases, SD 3 cases, the objective response rate (CR + PR) turned to be 57.1%, and the disease control rate (CR + PR + SD) was 100%. Among the 7 patients, except for one died of idiopathic thrombocytopenic, the others survived with no progression of liver disease. Overall survival time was being followed up. In respect of toxicity, no liver function abnormalities and radioactive hepatitis occurred; The 7 patients had mild symptom of nausea, vomiting, fatigue, loss of appetite and other gastrointestinal symptoms but no myelosuppression. The preliminary clinical results show that heavy ion is an effective and safe treatment method with mild side effect for hepatic malignances. It's suitable for patients with unresectable primary and secondary liver malignancies or those cannot tolerate surgery. Given the current shortage of cases and follow-up time, its long-term efficacy requires more cases and longer follow-up time to clarify. (authors)