title: Predictors of survival after radiofrequency thermal ablation of colorectal cancer metastases to the liver: a prospective study.
abstract: OBJECTIVE
  The aim of this study was to determine the predictors of survival at the time of radiofrequency thermal ablation (RFA) in patients with colorectal liver metastasis.
  
  
  METHODS
  One hundred thirty-five patients with colorectal liver metastases who were not candidates for resection underwent laparoscopic RFA.
  
  
  RESULTS
  The median Kaplan-Meier survival for all patients was 28.9 months after RFA treatment. Patients with a carcinoembryonic antigen (CEA) less than 200 ng/mL had improved survival compared with those with a CEA more than 200 (34 v 16 months; P = .01). Patients with the dominant lesion less than 3 cm in diameter had a median survival of 38 v 34 months for lesions 3 to 5 cm, and 21 months for lesions greater than 5 cm (P = .03). Survival approached significance for patients with one to three tumors versus more than three tumors (29 v 22 months; P = .09). The presence of extrahepatic disease did not affect survival. Only the largest liver tumor size more than 5 cm was found to be a significant predictor of mortality by Cox proportional hazards model, with a 2.5-fold increased risk of death versus the largest liver tumor size less than 3 cm (P = .05).
  
  
  CONCLUSIONS
  This study determines which patients do best after RFA. Historical survival with chemotherapy alone is 11 to 14 months, suggesting RFA has a positive impact on overall survival. Limited amounts of extrahepatic disease do not appear to affect survival adversely. RFA is a useful adjunct to chemotherapy in those patients with liver-predominant disease.
authors.affiliation: Department of General Surgery and Hematology & Medical Oncology, The Cleveland Clinic Foundation, 9500 Euclid Ave, Cleveland, OH 44195, USA.
authors.forename: Eren
authors.initials: E
authors.lastname: Berber
authors.forename: Robert
authors.initials: R
authors.lastname: Pelley
authors.forename: Allan E
authors.initials: AE
authors.lastname: Siperstein
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology* / Q000601:surgery*; D000368:Aged; D002272:Carcinoembryonic Antigen / Q000097:blood; D017115:Catheter Ablation / Q000379:methods; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D010535:Laparoscopy; D008113:Liver Neoplasms / Q000401:mortality / Q000556:secondary* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015996:Survival Rate
chemical_list: D002272:Carcinoembryonic Antigen