title: Incidence and treatment of local site recurrences following RFA of colorectal liver metastases.
abstract: BACKGROUND
  Patients with colorectal liver metastases (CRLM) who are ineligible for curative surgery are potential candidates for radiofrequency ablation (RFA). Although RFA has emerged as a well accepted and documented treatment modality, there are still some reservations because of initially high rates of local site recurrences (LSR). The aim of the present study was to evaluate LSR levels following RFA treatment, with a specific focus on re-treatment and survival.
  
  
  METHODS
  All patients ineligible for curative resection of CRLM and undergoing RFA alone or in combination with resection were prospectively included from July 2000 to December 2010 and retrospectively analyzed. Patients with untreatable extrahepatic disease were excluded. FDG PET-CT was conducted at 3-6 month intervals after RFA. Patients with LSR were evaluated for re-treatment.
  
  
  RESULTS
  A total of 132 patients were treated with RFA, which was combined with resection in 64 patients. A total of 290 lesions were ablated, with a mean number of 2.19 per patient and a mean size of 2.2 cm. Median survival was 41 months, with a 3- and 5-year survival of, respectively, 60 and 30.8 %. Following initial RFA, 39 patients developed an LSR in 40 ablated lesions, and local recurrence was strongly related to lesion size. Re-treatment could be performed in 26/39 patients, of whom eight remained disease-free.
  
  
  CONCLUSIONS
  Radiofrequency ablation can be applied to CRLM of less than 3 cm with curative intent. In the absence of extensive intrahepatic or extrahepatic disease, renewed treatment of local recurrences should be considered and is often successful.
authors.affiliation: Department of Surgery, VUmc Medical Centre, De Boelelaan 1117, 1081 HV, Amsterdam, The Netherlands. k.nielsen@vumc.nl
authors.forename: Karin
authors.initials: K
authors.lastname: Nielsen
authors.forename: Aukje A J M
authors.initials: AA
authors.lastname: van Tilborg
authors.forename: Martijn R
authors.initials: MR
authors.lastname: Meijerink
authors.forename: Matessa O
authors.initials: MO
authors.lastname: Macintosh
authors.forename: Babs M
authors.initials: BM
authors.lastname: Zonderhuis
authors.forename: Elly S M
authors.initials: ES
authors.lastname: de Lange
authors.forename: Emile F I
authors.initials: EF
authors.lastname: Comans
authors.forename: Sybren
authors.initials: S
authors.lastname: Meijer
authors.forename: M Petrousjka
authors.initials: MP
authors.lastname: van den Tol
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017115:Catheter Ablation; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D015994:Incidence; D008113:Liver Neoplasms / Q000175:diagnosis / Q000556:secondary* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009364:Neoplasm Recurrence, Local; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome