title: Percutaneous radiofrequency ablation using internally cooled wet electrodes for treatment of colorectal liver metastases.
abstract: OBJECTIVE
  To evaluate the efficacy and safety of internally cooled wet (ICW) electrodes, which provide interstitial infusion of saline and intra-electrode cooling simultaneously, in the percutaneous radiofrequency ablation (RFA) of liver metastases from colorectal cancer.
  
  
  METHODS
  From February 2008 to October 2010, 27 patients with 35 hepatic metastatic lesions (mean size 1.99cm; range 0.7-3.8cm) underwent RFA using ICW electrodes. Of these 35 tumours, 32 had diameters ≤3cm, and three had diameters of 3-4cm. Moreover, 18 tumours were non-subcapsular and 17 were subcapsular.
  
  
  RESULTS
  No patients (0%) had major complications after RFA. During follow-up (median 27 months; range 4.5-36 months), 14 of the 35 treated lesions (40%) showed local tumour progression. The local tumour progression-free survival rates at 1 and 3 years were 73 and 56%, respectively. The local tumour progression-free survival period was significantly longer in patients with tumours ≤2cm than >2cm (p<0.001), but did not differ significantly between patients with non-subcapsular and subcapsular tumours (p=0.454). The overall 1 and 3 year survival rates after RFA were 100 and 77%, respectively.
  
  
  CONCLUSIONS
  Percutaneous RFA using ICW electrodes is safe and technically feasible for the treatment of liver metastases from colorectal cancer. It provides effective local tumour control with low complication rates and reduced number of needle placements.
authors: Department of Radiology and Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Songpa-gu, Seoul, Republic of Korea.
authors: H M
authors: HM
authors: Yoon
authors: J H
authors: JH
authors: Kim
authors: Y M
authors: YM
authors: Shin
authors: H J
authors: HJ
authors: Won
authors: P N
authors: PN
authors: Kim
mesh_terms: D017115:Catheter Ablation / Q000379:methods*; D015179:Colorectal Neoplasms / Q000532:radiotherapy*; D018572:Disease-Free Survival; D005500:Follow-Up Studies; D006801:Humans; D008113:Liver Neoplasms / Q000532:radiotherapy* / Q000556:secondary; D047368:Tumor Burden