Randomized controlled trial for the efficacy of hepatic arterial occlusion during radiofrequency ablation for small hepatocellular carcinoma - direct ablative effects and a long-term outcome

To evaluate the efficacy of temporary balloon arterial occlusion during radiofrequency ablation (RFA), randomized controlled trial was performed. Twenty patients with hypervascular hepatocellular carcinoma measuring <= 30 mm were randomly treated with RFA combined with arterial occlusion (group A), or RFA alone (group B). Tumour ablation was performed in both groups using our 'stepwise hook extension technique.' Median diameters of the longer and shorter axis of RF-induced area measured on computer tomography were 38 mm (range, 31-52) and 36 mm (25-40) in group A, and 34 mm (26-45) and 26 mm (22-32) in group B respectively. Although the longer axis was not statistically significant, the shorter axis of group A was significantly larger than in group B (P=0.003). The median volume of the ablated lesion was 25.3 cm(3) (15.6-48.7) in group A and 16.1 cm(3) (9.3-23.8) in group B. The lesion volume was significantly larger in group A than in group B (P=0.005). The time and energy requirement of RFA of both groups were not significantly different. In addition, no serious adverse effects were observed in both groups. Intrasubsegmental tumour recurrence was found in 0% in group A and 30% in group B at the end of the third year (P=0.082). Hepatic arterial balloon occlusion during RFA is useful for extending the area of ablation in RF-induced lesions, and the procedure tended to decrease tumour recurrence from the same subsegment of ablated tumour.