title: The Outcome of Radiofrequency Ablation of Metastatic Liver Tumors.
abstract: OBJECTIVE
  To determine outcome of radiofrequency ablation (RFA) in metastatic liver tumor and to evaluate related factors of residual or local tumor recurrences.
  
  
  METHODS
  With Institutional Review Board approval, we retrospectively reviewed RFA procedure between June 2006 and September 2013. Fifty-seven metastatic nodules in 36 patients were treated. The primary tumors were colorectal carcinoma (n = 30), neuroendocrine tumor (n = 2), gallbladder carcinoma (n = 1), adenocarcinoma of head of pancreas (n = 1), and gastrointestinal stromal tumor (n = 2). Tumor characteristics, RFA techniques, success rate, complication, and follow-up imaging were reviewed and recorded Clinical outcome and overall survival were analyzed.
  
  
  RESULTS
  Complete ablation were found in 48/57 nodules (84.2%). The mean follow-up time was 17.9 ± 13.1 months (range, 1 to 47 months). Local tumor recurrence were noted in 12/57 nodules (21.1%), which mean time to recurrence was 8.3 ± 3.8 months (2 to 15 months). Residual tumor was associate with tumor larger than 3 cm (p = 0.009). The 1-, 3-, and 5-year overall survival rates were 93.6%, 56.2%, and 20%, respectively. Median overall survival was 37.8 ± 10.9 months. Major complication rate occurred about 5.3%.
  
  
  CONCLUSIONS
  Radiofrequency ablation is effective and feasible method to treat small metastatic liver tumor Tumor size larger than 3 cm is significant risk factor of residual tumor. Tumor in high-risk location is not associated either incomplete ablation or local tumor recurrence.
authors.forename: Somrach
authors.initials: S
authors.lastname: Thamtorawat
authors.forename: Satit
authors.initials: S
authors.lastname: Rojwatcharapibarn
authors.forename: Trongtum
authors.initials: T
authors.lastname: Tongdee
authors.forename: Thanongchai
authors.initials: T
authors.lastname: Siriapisith
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000601:surgery*; D018365:Neoplasm, Residual / Q000601:surgery*; D012189:Retrospective Studies; D016896:Treatment Outcome