Experimental Study on the Safety of Percutaneous Transhepatic Portal Vein Ablation.

BACKGROUND/AIMS:Portal vein tumor thrombus (PVTT) is a common complication of hepatocellular carcinoma (HCC) with poor prognosis. Radiofrequency ablation (RFA) has been used for PVTT, however, its safety remains unclear. In this study, we have evaluated the safety of percutaneous transhepatic RFA of pigs' normal portal vein (PV).METHODOLOGY:RFA was conducted in miniature pigs either by local direct ablation (group A, n=6), or after occlusion by balloon or by thrombus (group B, n=4). The MRI imaging and pathological changes of PV were recorded after operation.RESULTS:RFA was successful in 4 of 6 pigs in group A and 3 of 4 pigs in group B. One pig (P4) died one day after RFA in group A. P1 showed a significantly increased thrombus in peritoneal cavity in contrast to another survived pig (P2) with inflammatory edema, but no obvious abnormalities were observed in the other two pigs (P1 and P3) in Group A. But in Group B, the range of PV lesion was larger than that in Group A with thrombus in lumens, and even inflammatory edema range increased significantly 3 weeks later.CONCLUSION:The percutaneous intravascular RFA using an endovascular bipolar RF device is technically feasible but the safety needs further investigation.