Effect Of Hepatic Blood Inflow Occlusion On Radiofrequency Ablation Of The Liver Cancer

AIM: This study determined the impact of vascular occlusion of hepatic blood inflow on radiofrequency lesion and the liver injury in rabbit VX2 tumor model. To evaluate the HIF-1αand PCNA expression of the residual tumor when radiofrequency ablation was combined with hepatic blood inflow occlusion.METHODS: Rabbit VX2 liver tumor model were successfully established, and than they were assigned to two groups: radiofrequency ablation alone; radiofrequency ablation combined with hepatic blood inflow occlusion (vascular-occluded RFA). Radiofrequency lesions were created in vivo using a cool-tip radiofrequency electrode (radiofrequency parameters were time 8 min; power 30W). The hepatic blood flow occlusion was performed by Pringle maneuver. Serum ALT,AST,AKP,GGT was detected before the operation and the 1st,3 rd,7th day after the operation, and the adverse events was observed . The animals were sacrificed one week later. The size,volume of necrosis lesions in the two groups were then analyzed. Hypoxia-inducible factor-1α(HIF-1α) and proliferating cell nuclear antigen(PCNA) expression of the residual tumor were examined by immunohistochemistry.RESULTS: Volume and vertical diameter of the coagulated area was greater with the Pringle maneuver, and the differences were significant. The Parallel diameter is larger than that coagulated by standard RFA, but there are no significantly differences between the groups. Serum ALT,GGT was higher when radiofrequency ablation combined with Pringle maneuver than radiofrequency ablation alone at each time after the operation(P < 0.05), and serum GGT lever was gradually increased postoperatively. Differences of serum AST,AKP between the two groups at each time postoperatively were no significant. One case in vascular-occluded RFA group was complicated with mild bile leakage, one case died on the 1st day for hemorrhage, one case died for liver injury on the 4th day. The HIF-1αexpression of the residual carcinoma in the Group vascular-occluded RFA is higher than that in Group RFA alone, the difference is significant(P<0.05). Difference of the PCNA expression of the residual carcinoma in the two groups is no significant.CONCLUSION: Radiofrequency ablation combined with occlusion of the hepatic blood inflow increases the volume of necrosis when compared with radiofrequency ablation alone, but much more serious liver injury was found, careful attention should be paid when this technique is used in clinical practice. Vascular-occluded RFA may influence residual tumor invasion and metastasis.