AIM:To determine the feasibility of performingcomputed tomography(CT)-guided transpulmonaryradiofrequency ablation(RFA)for hepatocellularcarcinoma(HCC)located in the hepatic dome.METHODS:A total of seven patients with HCCcomprising seven nodules located in the hepatic domewere treated from April 2004 to December 2004.CT-guided transpulmonary RFA was performed using acool-tip type electrode(Radionics Company)based ona standardized energy protocol.All tumors located inthe hepatic dome were not detectable by the usualultrasound(US)methods.The lesion diameters rangedfrom 15 to 27 mm.RESULTS:RFA was technically feasible in all thepatients.The puncture procedure was performed twiceor less and the total average performance time was40.6 min.Local tumor control was achieved in all thepatients.The necrosis diameter ranged from 25 to35 mm.The mean follow-up period was 9.6(7-14 mo)mo.There was no local recurrence at the follow-uppoints.Pneumothorax requiring pleural drainage was themain complication,which was observed in two of theseven patients(28.6%).However,it improved with chestdrainage tube,and the tube could be removed within2-3 d.No other major complications were observed. CONCLUSION:CT-guided puncture is useful for thetreatment of tumors located in the hepatic dome whichare hardly detectable by US,even though pneumothoraxsometimes may occur as a complication.In the caseswith adhesion in the pleura for which artificial pleuraleffusion methods are not appropriate,CT-guided RFA isthus considered to be an alternative treatment for HCClocated in the hepatic dome. AIM: To determine the feasibility of performingcomputed tomography (CT) -guided transpulmonaryradiofrequency ablation (RFA) for hepatocellular carcinoma (HCC) located in the hepatic dome. METHODS: A total of seven patients with HCC comprising seven nodules located in the hepatic domewere treated from April 2004 to December 2004. CT-guided transpulmonary RFA was performed using acool-tip type electrode (Radionics Company) based on a standardized energy protocol. All tumors located in hepatic dome were not detectable by the usualultrasound (US) methods. The lesion diameters rangedfrom 15 to 27 mm.RESULTS: RFA was technically feasible in all the patients. The puncture procedure was performed twice or less and the total average performance time was 40.6 min. Local tumor control was achieved in all the patients. The necrosis diameter ranged from 25 to 35 mm. mean follow-up period was 9.6 (7-14 mo) mo.There was no local recurrence at the follow-uppoints.Pneumothorax requiring pleural drainage was the major complicati on, which was observed in two of theseven patients (28.6%). However, it improved with chest drainrain, and the tube could be removed within2-3 d.No other major complications were observed. CONCLUSION: CT-guided puncture is useful for thetreatment of tumors located in the hepatic dome whichare hardly detectable by US, even though pneumothorax may occur as a complication.In the cases with adhesion in the pleura for artificial leiomyocytes method are not appropriate, CT-guided RFA is considered as be an alternative treatment for HCClocated in the hepatic dome.