76 �� 1.12 in group A, and 3.36 �� 1.60 in group B (P = 0.01). The tumor considering necrosis rate at 1 mo post-RFA was 90.67% (68/75 lesions) in group A and 90.20% (92/102 lesions) in group B. HCC recurrence rate at 6 mo post-RFA was 17.33% (13/75) in group A and 31.37% (32/102) in group B (P = 0.04). CONCLUSION: PAA blocked effectively the feeding artery of HCC. Combination of PAA and RFA significantly decreased post-RFA recurrence and provided an alternative treatment for hypervascular HCC. Keywords: Hepatocellular carcinoma, Feeding artery, Radiofrequency ablation, Recurrence, Color Doppler flow imaging INTRODUCTION Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world (564 000 cases per year) and the third most frequent cause of cancer-related death[1].

Surgical resection is considered to be potentially curative therapy. However, only about 20% of HCC patients are eligible for resection[1,2]; the remainder are ineligible because of multifocal tumors, advanced tumors, tumor location precluding complete resection, or poor hepatic functional reserve. Therefore, a variety of imaging-guided tumor ablation therapies such as ethanol injection, microwave coagulation, percutaneous radiofrequency ablation (RFA) and laser ablation are often considered as alternative options[3�C6]. Among them, RFA has been used increasingly as a safe technique for treating hepatic tumors[7�C9]. However, for hypervascular HCC, RFA appears less effective because of a blood-flow-induced heat sink effect, which might cause incomplete ablation or recurrence[10].

Transcatheter arterial chemoembolization (TACE) can reduce blood supply of HCC by occlusion of tumor arteries, and the efficacy Anacetrapib of combination TACE and RFA has been confirmed[11,12]. Treatment difficulty remains for those patients who cannot tolerate or are ineligible for TACE because of liver cirrhosis or difficulty in manipulation of vessels with abnormal curvature that have resulted from surgical resection and liver transplantation. We hypothesized that, if percutaneous ablation of the feeding artery (PAA) of HCC could block or reduce the blood flow of HCC, the ablation volume of coagulation necrosis of subsequent RFA of the tumor would be increased. To the best of our knowledge, the application of PAA in the treatment of hypervascular HCC has not been reported in a large number of patients. In the present study, we evaluated the feasibility and adjuvant value of PAA performed before routine RFA treatment (PAA-RFA) of hypervascular HCC. MATERIALS AND METHODS Patients From January 2003 to June 2007, patients with HCC who met the entry criteria and agreed to participate were included in the study.