Conventional fractionated helical tomotherapy for patients with small to medium hepatocellular carcinomas without portal vein tumor thrombosis

BACKGROUND The purpose of this study was to evaluate clinical outcomes of conventional fractionated helical tomotherapy in patients with small to medium hepatocellular carcinomas (HCCs) without portal vein tumor thrombosis. METHODS Patients with up to four HCC lesions not treatable by surgery or percutaneous ablative therapies, <10 cm in the longest diameter, and no evidence of major vascular invasion were included. From January 2008 to January 2013, 20 patients with 33 tumors met the eligibility criteria and received definitive or salvage helical tomotherapy. The most commonly prescribed dose fractionation schedule was a total dose of 50 Gy with a daily dose of 2.5 Gy. Treatment response, survival, and radiation-induced toxicities were retrospectively reviewed. RESULTS The median follow-up period after radiotherapy for all patients was 24.9 (range 7.8-79.2) months. Objective responses (complete response or partial response) occurred in 30 of 33 lesions (90.9%). Eight (24.2%) lesions showed local recurrence and the actuarial local control rate at 2 years was 69.5%. Intrahepatic recurrence-free survival and overall survival rates at 2 years were 45.7% and 71.1%, respectively. Age, Child-Pugh class, tumor response, local recurrence status, and intrahepatic recurrence status were significantly associated with overall survival on univariate analysis. Among these parameters, only local recurrence status showed marginal statistical significance on multivariate analysis (P=0.068). The overall survival rate at 2 years was 50% for patients who experienced local recurrence, but 87.5% for those who did not. No patient experienced grade 2 or greater general or gastrointestinal toxicity. There were no cases of radiation-induced liver disease. CONCLUSION Conventional fractionated helical tomotherapy for patients with less than four small to medium HCCs without portal vein tumor thrombosis yielded favorable local control and overall survival without severe complications.