title: Selection criteria for radiofrequency ablation for colorectal liver metastases in the era of effective systemic therapy: a clinical score based proposal.
abstract: BACKGROUND
  At present, there are no widely accepted criteria for the use of radiofrequency ablation (RFA) for the treatment of colorectal liver metastases (CLM) in the context of effective modern-agent therapies. We aimed to define selection criteria for patients with liver-limited CLM who may benefit from adding RFA to systemic therapy with respect to long-term disease control.
  
  
  METHODS
  Between 2002 and 2007, 88 consecutive patients received RFA for liver-only CLM during partial remission (PR), stable disease (SD), or progressive disease (PD) after systemic therapy. At a median follow-up of 8.2 years (range 5.2-11.1 years), clinical data were correlated to overall survival (OS) and recurrence-free survival (RFS).
  
  
  RESULTS
  Poor OS and RFS correlated significantly with PD to systemic therapy before RFA (HR 5.46; p < 0.0001; and HR 6.46; p < 0.0001), number of ≥4 CLM (HR 3.13; p = 0.0005; and HR 1.77; p = 0.0389), and carcinoembryonic antigen (CEA) level of ≥100 ng/ml (HR 1.67; p = 0.032; and HR 1.67; p = 0.044). The presence of four criteria (PR, ≤3 CLM, ≤3 cm maximum size, and CEA ≤100 ng/ml) selected a subgroup (n = 23) with significantly higher probabilities for OS and RFS at 5 years (39% and 22%,respectively) compared to those without any or up 3 of these criteria (0-27% and 0-9%, p < 0.001, respectively).
  
  
  CONCLUSIONS
  A score based on four criteria (response to systemic therapy, ≤3 CLM, ≤3 cm size, low CEA value) may allow to select patients with liver-only CLM for whom additional use of RFA most likely adds benefit in an attempt to achieve long-term disease control. Almost one-fourth of patients fulfilling these four criteria may achieve 5-year survival without disease recurrence following effective systemic plus local RFA treatment.
authors.affiliation: Department of Hematology and Oncology, Asklepios Hospital Barmbek, Rübenkamp 220, 22291 Hamburg, Germany. a.stang@asklepios.com.
authors.forename: Axel
authors.initials: A
authors.lastname: Stang
authors.forename: Karl Jürgen
authors.initials: KJ
authors.lastname: Oldhafer
authors.forename: Hauke
authors.initials: H
authors.lastname: Weilert
authors.forename: Handan
authors.initials: H
authors.lastname: Keles
authors.forename: Marcello
authors.initials: M
authors.lastname: Donati
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation / Q000379:methods*; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology* / Q000556:secondary / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome