A case of tumor seeding after percutaneous radiofrequency ablation for hepatocellular carcinoma

Abstract

We report a case of tumor seeding after percutaneous radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). A 56-year-old woman who had previously undergone RFA with 2 insertions of a cooled-tip electrode to 28 x 20 mm subcapsular HCC in liver segment VII was found 9 months later in abdominal computed tomography to have a small, mild contrast-enhanced mass outside the hypodense area of the RFA, so partial hepatectomy was done based on a diagnosis of HCC recurrence. Macroscopically, 2 tumors measured 7 x 6 mm and 3 x 3 mm. Histopathologically, the 2 well-differentiated HCC tumors existed in a layer of fatty tissue near the completely necrosed tissue of the ablated area. The final diagnosis of tumor seeding was determined because no contact was seen between the 2 tumors, consistent with 2 insertions, and the ablated area. We are now studying how to manage the prevention of tumor seeding after RFA.