Comparison of percutaneous radiofrequency ablation and CyberKnife® for initial solitary hepatocellular carcinoma: A pilot study

AIM: To compare therapeutic outcomes and adverse events in initial solitary hepatocellular carcinoma (HCC) treated with radiofrequency ablation (RFA) and CyberKnife (R). METHODS: Seventy three consecutive patients with initial solitary HCC treated with RFA (38 patients; RFA group) and CyberKnife (R) (35 patients; CK group) were enrolled in this study. Background groups. Local and intrahepatic distant recurrence control, and cumulative survival rates were compared between the two groups. These were determined using the Kaplan-Meier method, and the significance of differences was analyzed by log-rank test. The presence of more grade 3 on CTCAE ver. 4.0 early and late adverse events was investigated. RESULTS: In background factors, age was significantly higher (P = 0.005) and the tumor diameter was significantly larger (P = 0.001) in the CK group. The 1-year local recurrence control rates were 97.4% and 97.1% in the RFA and CK groups, respectively (P = 0.71); the 1-year intrahepatic distant recurrence control rates were 85.6% and 86.1%, respectively (P = 0.91); and the 1-year cumulative survival rates were 100% and 95.2%, respectively (P = 0.075), showing no significant difference in any rate between the two groups. There were no late adverse event in the RFA group, but 11.4% in the CK group had late adverse events. In the CK group, the Child-Pugh score at 12 mo after treatment was significantly higher than that in the RFA group (P = 0.003) and significantly higher than the score before treatment (P = 0.034). CONCLUSION: The occurrence of adverse events is a concern, but CyberKnife (R) treatment is likely to become an important option for local treatment of early HCC.