title: Radiofrequency ablation of small breast tumours: evaluation of a novel bipolar cool-tip application.
abstract: BACKGROUND
  Although radiofrequency ablation (RFA) is promising for the local treatment of breast cancer, burns are a frequent complication. The safety and efficacy of a new technique with a bipolar RFA electrode was evaluated.
  
  
  METHODS
  Dosimetry was assessed ex vivo in bovine mammary tissue, applying power settings of 5-15 W with 10-20 min exposure and 3.0-12.0 kJ to a 20-mm active length bipolar internally cooled needle-electrode. Subsequently, in 15 women with invasive breast carcinoma ≤2.0 cm diameter ultrasound-guided RFA was performed followed by immediate resection.
  
  
  RESULTS
  An ablation zone of 2.5 cm was reached in the ex vivo experiments at 15 W at 9.0 kJ administered energy. Histopathology revealed complete cell death in 10 of 13 patients (77%); in 3 patients partial ablation was due to inaccurate probe positioning. In 1 patient a pneumothorax was caused by the probe placement, treated conservatively. No burns occurred.
  
  
  CONCLUSIONS
  Ultrasound-guided RFA with a bipolar needle-electrode appears to be a safe local treatment technique for invasive breast cancer up to 2 cm. Ways to improve placement of the probe and direct monitoring of the ablation-effect should be the aim of further research.
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands. Electronic address: l.waaijer@umcutrecht.nl.
authors.forename: L
authors.initials: L
authors.lastname: Waaijer
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
authors.forename: D L
authors.initials: DL
authors.lastname: Kreb
authors.affiliation: Department of Radiology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
authors.forename: M A
authors.initials: MA
authors.lastname: Fernandez Gallardo
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
authors.forename: P S N
authors.initials: PS
authors.lastname: Van Rossum
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
authors.forename: E L
authors.initials: EL
authors.lastname: Postma
authors.affiliation: Department of Surgery, St. Antonius Hospital, Koekoekslaan 1, 3435 CM Nieuwegein, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Koelemij
authors.affiliation: Department of Pathology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
authors.forename: P J
authors.initials: PJ
authors.lastname: Van Diest
authors.affiliation: Department of Medical Technology and Clinical Physics, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
authors.forename: J H G M
authors.initials: JH
authors.lastname: Klaessens
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
authors.forename: A J
authors.initials: AJ
authors.lastname: Witkamp
authors.affiliation: Department of Surgery, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands.
authors.forename: R
authors.initials: R
authors.lastname: Van Hillegersberg
mesh_terms: D000368:Aged; D000818:Animals; D001943:Breast Neoplasms / Q000473:pathology / Q000601:surgery*; D002056:Burns / Q000517:prevention & control*; D018270:Carcinoma, Ductal, Breast / Q000473:pathology / Q000601:surgery*; D017115:Catheter Ablation / Q000295:instrumentation / Q000379:methods*; D002417:Cattle; D004566:Electrodes; D004867:Equipment Design; D005260:Female; D006801:Humans; D008321:Mammary Glands, Animal; D008875:Middle Aged
keywords: Breast cancer; Minimally invasive techniques; Radiofrequency ablation (RFA)