title: [Cryoablation--a treatment option for inoperable liver tumors?].
abstract: BACKGROUND
  Most patients with primary and secondary liver tumours are inoperable by conventional surgery. This has prompted the development of different techniques of local destruction of liver tumours, i.e. cryosurgical ablation radiofrequency, laser, and microwave ablation.
  
  
  METHODS
  On the basis of relevant literature and our own experience we describe the principles of local destruction by cryoablation of colorectal metastases.
  
  
  RESULTS
  Indications for ablation are mainly colorectal metastases and hepatocellular carcinoma. Mechanisms for tumour destruction include intra- and extracellular ice crystal formation, cellular membrane rupture, cellular dehydration and ischaemic damage. Ablation is regularly monitored by ultrasonography, which is suboptimal because of inadequate visualisation of the iceball. Long-term outcome of local destruction of liver tumours is not documented and randomized trials are not ethically acceptable. This complicates analyses of patient outcomes.
  
  
  CONCLUSIONS
  Local ablation of liver tumours is experimental therapy and should only be performed as a part of prospective trials.
authors.affiliation: Seksjon for gastroenterologisk kirurgi, Intervensjonssenteret, Rikshospitalet 0027 Oslo. tom.mala@rikshospitalet.no
authors.forename: T
authors.initials: T
authors.lastname: Mala
authors.forename: L
authors.initials: L
authors.lastname: Frich
authors.forename: B
authors.initials: B
authors.lastname: Edwin
authors.forename: E
authors.initials: E
authors.lastname: Samset
authors.forename: P K
authors.initials: PK
authors.lastname: Hol
authors.forename: E
authors.initials: E
authors.lastname: Fosse
authors.forename: Ø
authors.initials: Ø
authors.lastname: Mathisen
authors.forename: A
authors.initials: A
authors.lastname: Bergan
authors.forename: O
authors.initials: O
authors.lastname: Søreide
authors.forename: I
authors.initials: I
authors.lastname: Gladhaug
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D017115:Catheter Ablation / Q000009:adverse effects / Q000379:methods*; D015179:Colorectal Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary / Q000601:surgery*; D003452:Cryosurgery / Q000009:adverse effects / Q000379:methods*; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D008872:Microwaves / Q000627:therapeutic use; D016896:Treatment Outcome; D014463:Ultrasonography