title: Radiofrequency ablation of liver tumors: a novel needle perfusion technique enhances efficiency.
abstract: OBJECTIVE
  We hypothesize that perfusion of an expandable radiofrequency ablation (RFA) needle with saline solution might help prevent charring and increase efficiency.
  
  
  BACKGROUND
  RFA has become an important adjunct to modern liver surgery. However, ablation is time-consuming and hazardous due to charring around the radiofrequency electrodes.
  
  
  METHODS
  From June 2000 to November 2004, 159 liver tumors with a median diameter of 2.0 cm were treated with RFA, 54 tumors of them according to the manufacturer's standard protocol and 105 tumors according to the novel perfusion protocol. No randomization was applied. All patients were followed up with contrast enhanced computed tomography (CT) at regular intervals. Local recurrence was defined as radiologic and/or histologic evidence of viable tumor within or at the ablated liver area.
  
  
  RESULTS
  Both study groups were comparable with regard to tumor characteristics, procedure related complications, and median times of follow-up (27 mo in the standard group versus 23 mo in the perfusion group). The median RFA time was significantly reduced from 18.9 min in the standard group to 8.0 min in the perfusion group. The rates of incomplete ablations were comparable in both groups (3.7% versus 2.8%). The rate of local recurrences at the RFA site was 6.9% overall, 11.1% in the standard group, and 4.8% in the perfusion group. No tumor seeding along the puncture channel was observed.
  
  
  CONCLUSIONS
  The perfusion of an expandable RFA needle with saline solution significantly accelerates the ablation procedure of liver tumors without increase of complications and without compromising the oncosurgical result.
authors.affiliation: Clinic for General, Visceral, Vascular, and Thoracic Surgery Hospital of Liestal, affiliated hospital of the University of Basel, Liestal, Switzerland.
authors.forename: Paolo
authors.initials: P
authors.lastname: Abitabile
authors.forename: Christoph A
authors.initials: CA
authors.lastname: Maurer
mesh_terms: D055011:Ablation Techniques; D002277:Carcinoma / Q000453:epidemiology / Q000601:surgery*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000453:epidemiology / Q000601:surgery*; D008297:Male; D009339:Needles; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology*; D010477:Perfusion; D013557:Switzerland / Q000453:epidemiology; D013997:Time Factors