Objective To explore efficacy and safety of radiofrequency ablation (RFA) in the treatment of large hepatocarcinoma. MethodsFortythree cases of large hepatocarcinoma underwent RFA with the expandable cluster electrode,eight of all cases had undergone transcatheter artery chemoembolization (TAE) for 1-2 sessions within 2 months before RFA; the tumors were 5-10 cm in diameter, mean 7.5 cm. Hepatic function examination, alphafetoprotein, enhanced CT scans,color ultrasonography and needle biopsy were performed,pre and posttreatment. Complete necrosis was evaluated by dynamic enhanced CT scans and biopsy. Therapeutic time and sessions of RFA,length of stay in hospital and complications of RFA were observed; and thirtynine of 43 cases after RFA were followed up for 12-18 months.ResultsFortythree cases of large hepatocarcinoma received RFA for 67 sessions, 1-3 sessions per case,mean 1.6 sessions; therapeutic time 55-150 min,mean 75 min; length of stay in hospital 3-15 day, mean 8.7 day; major complications of RFA included local skin burn of electrode board in 2 cases (4.6%) and moderatetolarge right pleural effusion in 3 cases (7.0%),overall complications rate was 11.6%; complete necrosis was achieved in 41.0% of cases which were evaluated by dynamic enhanced CT scans at least 6 months followed RFA; of thirtyone cases of positive AFP, AFP level became negative in 3,decreased obviously in 5 within 6-12 months after RFA; in 12-18 months followup,oneyear survival rate was 69.2%.Conclusion RFA appears to be safe, effective and minor invasive for the treatment of large hepatocarcinoma.