Radiofrequency ablation versus resection for liver tumours: an evidence-based approach to retrospective comparative studies.
BACKGROUND
Recently randomized controlled trials have been advocated to compare radiofrequency ablation (RFA) and hepatic resection (HR) in resectable tumours and determine whether differences in observed survivals result from the heterogeneity in previous studies between RFA (treating unresectable lesions) and HR (treating lesions deemed resectable). We reviewed the literature that directly compares the treatments and employed an evidence-based approach to examine the data.


METHODS
All studies comparing RFA and HR were included. Primary outcomes were the overall survival (OS) and disease-free survival (DFS) at 3 and 5 years. A subgroup analysis was conducted for solitary or small tumors (<4 cm for colorectal metastases (CRM) or <5 cm for hepatocellular carcinoma (HCC)).


RESULTS
Most studies were retrospective. For CRM, HR was markedly superior to RFA in respect of 3- and 5-year OS as well as 5-year DFS including tumours smaller than 4 cm and solitary lesions. For HCC, HR was markedly superior to RFA for 3- and 5-year OS as well as 3-year DFS, and produced a better OS at 3 years for solitary lesions and DFS at 3 years for small tumours.


CONCLUSIONS
Multiple factors determine outcomes following treatment of liver tumours. Small or solitary lesions seem the most appropriate ones to study as this reduces the number of confounding variables, but even in these cases HR confers a better OS and DFS than RFA for both CRM and HCC. If our data are confirmed it will be important to examine other factors influencing the response.
Department of Hepatobiliary and Pancreatic Surgery, Leicester General Hospital, Gwendolen Road, Leicester, LE5 4PW, UK. ggravante@hotmail.com
Gianpiero
G
Gravante
John
J
Overton
Roberto
R
Sorge
Neil
N
Bhardwaj
Matthew S
MS
Metcalfe
David M
DM
Lloyd
Ashley R
AR
Dennison
D006528:Carcinoma, Hepatocellular / Q000601:surgery*; D017115:Catheter Ablation; D015179:Colorectal Neoplasms / Q000473:pathology; D018572:Disease-Free Survival; D019317:Evidence-Based Medicine; D006498:Hepatectomy; D006801:Humans; D008113:Liver Neoplasms / Q000473:pathology / Q000556:secondary* / Q000601:surgery*; D012189:Retrospective Studies; D015996:Survival Rate