Interventional Radiology - Original Article

Overcoming the heat-sink phenomenon: successful radiofrequency thermal ablation of liver tumors in contact with blood vessels

  • Loukas Thanos
  • Sophia Mylona
  • Panagiota Galani
  • Maria Pomoni
  • Anastasia Pomoni
  • Ioannis Koskinas

Received Date: 06.08.2007 Accepted Date: 03.10.2007 Diagn Interv Radiol 2008;14(1):51-56


To evaluate the efficacy and safety of computed tomography (CT)-guided radiofrequency thermal ablation (RFA) of liver tumors (hepatocellular carcinoma and liver metastases) >3 mm in diameter that were in contact with blood vessels.


During a 3-year period RFA was performed in 28 patients (age range, 36–83 years; male/female ratio, 17:11) with liver tumors (primary and metastatic) that were in contact with blood vessels >3 mm in diameter. Tumor diameter ranged from 1.7 to 5.1 cm. To evaluate the immediate response, dual-phase dynamic CT images were obtained after intravenous contrast material administration. Imaging follow-up was at 1, 3, 6, and 12 months post-RFA, and every year thereafter.


All of 28 patients were treated with a total of 36 sessions. In 22 (79%) of the patients, complete ablation of the tumor was achieved. The remaining 6 (21%) patients showed irregular peripheral enhancement and underwent a second session. At 1-year follow-up 2 of the tumors showed a recurrent lesion and a new ablation was performed. The local tumor progression rate at 1-year follow-up was 8.7% and disease-free survival was achieved in 82.1% of the patients. Complications occurred in 4 patients (14.3%); 2 patients presented with a small sub-capsular hematoma, and 2 patients had a partial liver infarction.


RFA is a safe and effective method, even with highrisk tumors adjacent to large blood vessels, which can lead to good results with minimal complications and a low rate of tumor progression.

Keywords: liver tumors • radiofrequency thermal ablation • percutaneous catheter ablation