Authors' objectives:

The aim of this review was to assess the efficacy and safety of radiofrequency ablation (RFA) of liver tumors.

Authors' results and conclusions: A revision carried out by ASERNIP-S (Australian Agency) and published by the National Institute for Clinical Excellence (NICE) of England, based mainly on a systematic revision undertaken by Sutherland et al was identified. Besides, a controlled, randomized clinical trial published (CRCT) by Lin et al was identified after this revision. Sutherland describes a CRCT comparing RFA and a percutaneous ethanol injection (PEI). No differences were observed in mortality at one and two years (0% and 2% versus 4% and 12%) when comparing both techniques. On the other hand, Lin's work shows longer survival with RFA than with PEI. Sutherland observed that there was a tendency towards less local post-treatment recurrence (RR 0.24, CI 95% 0.05 - 1.04), with a median follow-up of 14 months, and a better long-term tumor control (a 16 month median follow-up) for RFA than for PEI (RR 1.23, CI95% 1.02 - 1.50). He also observed more survival without local recurrence for RFA (98% and 96%) than for PEI (83% and 62%). Lin's et al study shows similar results at one, two and three years of follow-up. When evaluating safety measures, more adverse effects were observed with RFA than with PEI (fever, pain and analgesics need). The length of hospital stay assessed in a CRCT was shorter for RFA than for PEI (p<0.01), although operative times were longer. As regards surgical resection, the rates of recurrence and the presence of residual disease were significantly higher with RFA than with the surgical treatment. Sutherland et al describe a quasi-experimental study, in which in a 38-month follow-up, and in cases where the tumor diameter was less than 3.5 cm., recurrence in the patients who underwent surgery was 14%, whereas in those treated with RFA, it was 39% (p<0.05). In the same revision, a CRCT is described which compares the use of RFA with microwave coagulation therapy (MCT). No significant differences were found at 18 months with respect to residual disease. In addition, fewer complications are described for RFA, without differences in major complications. On the other hand, a study which compared RFA with laser induced thermotherapyshowed that RFA presents a smaller proportion of residual nodules. Besides, complications such as arterioportal fistulas, liver infarct, focal atrophy and subcapsular fluid collections were also fewer for RFA. When comparing tumor growth control between RFA and a historic control group that used hepatic artery infusion chemotherapy, no statistically significant differences were found (50% vs 30%, p=NS). There were also, fewer complications with RFA than in the control group treated with chemotherapy. No differences are described with respect to mortality rates when RFA is compared with other techniques (except in the paper published by Lin et al). Several health organizations are considering the use of radiofrequency ablation of liver tumors when certain requirements are fulfilled: a) They are not candidates for surgical tumor resection (either because of local involvement, or because of the tumor location or comorbidities); b) there are metastases of an isolated colorectal cancer or a hepatocarcinoma; c) They do not have systemic or extrahepatic disease; d) identification images have been performed (ultrasound or computed tomography); and e) tumors are less than 4 cm in diameter. Those tumors of other origins which are treated with RFA or which are treated for palliative treatment are considered investigational.

Authors' recommendations: Most malignant liver tumors can not be surgically removed because of their extension, systemic involvement, comorbidities or tumor size. RFA is proposed as an alternative for patients with primary hepatocellular tumors or liver metastases of colorectal cancer, when surgery is not possible. When assessing the evidence, it is observed that in all cases tumor resection is the treatment of choice. When this is not possible, RFA shows more effectiveness than most alternative treatments. However, it is worth mentioning that the differences found are mainly in the rates of local recurrence and length of hospital stay, but there are no differences in survival. In addition, complications, although not evaluated by many authors, would be fewer than in other treatment alternatives (experts suggest a complication rate of 3% to 5%), with a mortality rate lower than 1%. To use this treatment, it is recommended that a multidisciplinary team including a liver surgeon performs a patient selection and that it is performed under ultrasound or topography guidance. The requirements that must be met to use RFA in patients with liver tumor are: - not candidates for surgical tumor resection (either because there is local involvement, or because of tumor location or comorbidities) - metastases of an isolated colorectal cancer or a hepatocarcinoma - no systemic or extrahepatic disease - identification images (ultrasound or computed tomography) - tumors less than 4 cm in diameter. Those tumors of other origins which are treated with RFA or which are treated for palliative treatment are considered investigational.

Authors' methods: Overview

Project Status: Completed

URL for project: http://www.iecs.org.ar/

Year Published: 2005

English language abstract: An English language summary is available

Publication Type: Not Assigned

Country: Argentina

Organisation Name: Institute for Clinical Effectiveness and Health Policy

Contact Address: Dr. Emilio Ravignani 2024, Buenos Aires - Argentina, C1414 CABA

Contact Name: info@iecs.org.ar

Contact Email: info@iecs.org.ar

Copyright: Institute for Clinical Effectiveness and Health Policy (IECS)