title: Cryosurgical ablation and radiofrequency ablation for unresectable hepatic malignant neoplasms: a proposed algorithm.
abstract: BACKGROUND
  Thermal ablation of unresectable hepatic tumors can be achieved by cryosurgical ablation (CSA) or radiofrequency ablation (RFA). The relative advantages and disadvantages of each technique have not yet been determined.
  
  
  OBJECTIVE
  Radiofrequency ablation of malignant hepatic neoplasms can be performed safely, but is currently limited by size. Cryosurgical ablation, while associated with higher morbidity, is more effective for larger unresectable hepatic malignant neoplasms.
  
  
  METHODS
  Retrospective analysis of prospective patient database.
  
  
  METHODS
  Between July 1992 and September 1999, 308 patients with liver tumors not amenable to curative surgical resection were treated with CSA and/or RFA (percutaneous, laparoscopic, celiotomy). No patient had preoperative evidence of extrahepatic disease. All patients underwent laparoscopy with intraoperative ultrasound if technically possible. Both RFA and CSA were performed under ultrasound guidance. Resection, as an adjunctive procedure, was combined with ablation in certain patients.
  
  
  RESULTS
  Laparoscopy identified extrahepatic disease in 12% of patients, and intraoperative hepatic ultrasound identified additional lesions in 33% of patients, despite extensive preoperative imaging. Radiofrequency ablation alone or combined with resection or CSA resulted in reduced blood loss (P<.05), thrombocytopenia (P<.05), and shorter hospital stay compared with CSA alone (P<.05). Median ablation times for lesions greater than 3 cm were 60 minutes with RFA and 15 minutes with CSA (P<.001). Local recurrence rates for lesions greater than 3 cm were also greater with RFA (38% vs 17%).
  
  
  CONCLUSIONS
  Laparoscopy and intraoperative ultrasound are essential in staging patients with hepatic malignant neoplasms. Radiofrequency ablation when combined with CSA reduces the morbidity of multiple freezes. Although RFA is safer than CSA and can be performed via different approaches (percutaneously, laparoscopically, or at celiotomy), it is limited by tumor size (<3 cm). Percutaneous RFA should be considered in high-risk patients or those with small local recurrences.
authors.affiliation: John Wayne Cancer Institute at Saint John's Health Center, Santa Monica, Calif 90404, USA. bilchika@jwci.org
authors.forename: A J
authors.initials: AJ
authors.lastname: Bilchik
authors.forename: T F
authors.initials: TF
authors.lastname: Wood
authors.forename: D
authors.initials: D
authors.lastname: Allegra
authors.forename: G J
authors.initials: GJ
authors.lastname: Tsioulias
authors.forename: M
authors.initials: M
authors.lastname: Chung
authors.forename: D M
authors.initials: DM
authors.lastname: Rose
authors.forename: K P
authors.initials: KP
authors.lastname: Ramming
authors.forename: D L
authors.initials: DL
authors.lastname: Morton
mesh_terms: D017115:Catheter Ablation; D003452:Cryosurgery; D005260:Female; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D008113:Liver Neoplasms / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000453:epidemiology; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome