title: Radiofrequency ablation of colorectal liver metastases.
abstract: BACKGROUND
  Untreated patients with colorectal liver metastases rarely survive 3 years, and the 3-year survival rate for patients treated with chemotherapy is 3%. The best survival rates are for the small subgroup that has operable disease, i.e., 39% at 5 years. Radiofrequency ablation (RFA) offers a new opportunity to destroy liver metastases in patients who are not surgical candidates because of disease distribution or comorbidity.
  
  
  METHODS
  Acceptance criteria were a maximum of four or five liver lesions with a maximum diameter of 4 or 5 cm and no evidence of active extrahepatic disease. Nearly all treatments were performed percutaneously using ultrasound, computed tomography, or magnetic resonance imaging (or some combination) for guidance and monitoring. RFA is a minimally invasive procedure that can be readily repeated. General anesthesia facilitates the procedure but is not essential. Multiple overlapping ablations are required to ensure optimal treatment in all but the smallest tumors.
  
  
  RESULTS
  In our cohort of 167 patients with colorectal liver metastases, 73 fulfilled the optimal acceptance criteria (5 or fewer tumors that were </=5 cm). The median survival periods were 38 months, with a 5-year survival rate of 30%, after the diagnosis of liver metastases and 31 months, with a 5-year survival rate of 25%, after the first ablation.
  
  
  CONCLUSIONS
  RFA increases the therapeutic options for patients with colorectal metastases. Until controlled trials can better define the role of RFA, there are several groups of patients who are not surgical candidates and can be considered for RFA.
authors.affiliation: Department of Medical Imaging, The Middlesex Hospital, Mortimer Street, London W1T 3AA, United Kingdom. a.gillams@medphys.ucl.ac.uk
authors.forename: A R
authors.initials: AR
authors.lastname: Gillams
authors.forename: W R
authors.initials: WR
authors.lastname: Lees
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation / Q000379:methods*; D017024:Chemotherapy, Adjuvant; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000556:secondary* / Q000601:surgery; D003287:Contrast Media; D005260:Female; D006801:Humans; D007023:Hypotension, Controlled; D008113:Liver Neoplasms / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures; D018579:Patient Selection; D011183:Postoperative Complications; D015641:Radiography, Interventional; D012004:Rectal Neoplasms / Q000556:secondary* / Q000601:surgery; D015996:Survival Rate; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
chemical_list: D003287:Contrast Media