title: CT-guided bipolar and multipolar radiofrequency ablation (RF ablation) of renal cell carcinoma: specific technical aspects and clinical results.
abstract: OBJECTIVE
  This study was designed to evaluate the clinical efficacy of CT-guided bipolar and multipolar radiofrequency ablation (RF ablation) of renal cell carcinoma (RCC) and to analyze specific technical aspects between both technologies.
  
  
  METHODS
  We included 22 consecutive patients (3 women; age 74.2 ± 8.6 years) after 28 CT-guided bipolar or multipolar RF ablations of 28 RCCs (diameter 2.5 ± 0.8 cm). Procedures were performed with a commercially available RF system (Celon AG Olympus, Berlin, Germany). Technical aspects of RF ablation procedures (ablation mode [bipolar or multipolar], number of applicators and ablation cycles, overall ablation time and deployed energy, and technical success rate) were analyzed. Clinical results (local recurrence-free survival and local tumor control rate, renal function [glomerular filtration rate (GFR)]) and complication rates were evaluated.
  
  
  RESULTS
  Bipolar RF ablation was performed in 12 procedures and multipolar RF ablation in 16 procedures (2 applicators in 14 procedures and 3 applicators in 2 procedures). One ablation cycle was performed in 15 procedures and two ablation cycles in 13 procedures. Overall ablation time and deployed energy were 35.0 ± 13.6 min and 43.7 ± 17.9 kJ. Technical success rate was 100 %. Major and minor complication rates were 4 and 14 %. At an imaging follow-up of 15.2 ± 8.8 months, local recurrence-free survival was 14.4 ± 8.8 months and local tumor control rate was 93 %. GFR did not deteriorate after RF ablation (50.8 ± 16.6 ml/min/1.73 m(2) before RF ablation vs. 47.2 ± 11.9 ml/min/1.73 m(2) after RF ablation; not significant).
  
  
  CONCLUSIONS
  CT-guided bipolar and multipolar RF ablation of RCC has a high rate of clinical success and low complication rates. At short-term follow-up, clinical efficacy is high without deterioration of the renal function.
authors.affiliation: Department of Diagnostic and Interventional Radiology, University Hospital Heidelberg, INF 110, 69120 Heidelberg, Germany. christof.sommer@med.uni-heidelberg.de
authors.forename: C M
authors.initials: CM
authors.lastname: Sommer
authors.forename: G
authors.initials: G
authors.lastname: Lemm
authors.forename: E
authors.initials: E
authors.lastname: Hohenstein
authors.forename: N
authors.initials: N
authors.lastname: Bellemann
authors.forename: U
authors.initials: U
authors.lastname: Stampfl
authors.forename: A S
authors.initials: AS
authors.lastname: Goezen
authors.forename: J
authors.initials: J
authors.lastname: Rassweiler
authors.forename: H U
authors.initials: HU
authors.lastname: Kauczor
authors.forename: B A
authors.initials: BA
authors.lastname: Radeleff
authors.forename: P L
authors.initials: PL
authors.lastname: Pereira
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D006801:Humans; D007677:Kidney Function Tests; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D015641:Radiography, Interventional / Q000379:methods*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome