Rapid and aggressive recurrence accompanied by portal tumor thrombus after radiofrequency ablation for hepatocellular carcinoma.

Although radiofrequency ablation (RFA) has been reported to be a safe and effective procedure for the treatment of hepatocellular carcinoma (HCC), patterns of recurrence and complications following RFA treatment have not been fully identified. Recently, we have experienced two cases of HCC patients who developed rapid and aggressive recurrence accompanied by portal tumor thrombus after RFA therapy. The first was a 68-year-old woman with hepatitis C virus (HCV)-positive liver cirrhosis, who received percutaneous RFA therapy for a 27-mm-diameter HCC in segment VII. The other was a 64-year-old man with hepatitis B surface antigen (HBsAg)-positive liver cirrhosis and multiple bilobar HCCs, who underwent left hemihepatectomy and intraoperative RFA for the two tumors in the remnant liver. In both patients, though immediate imaging studies suggested complete necrosis of the tumors, recurrences with massive portal tumor thrombus occurred in 4 and 6 months, respectively. At present, it is unclear whether such a recurrence pattern is directly related to the RFA procedure. However, it is implied that RFA therapy may entail a risk of promoting portal venous invasion of HCC tumors.