Authors' objectives: Around 15% to 30% of people with colorectal cancer have metastases on diagnosis, with approximately 20% to 50% going on to develop metastases within five years. The liver is one of the most common sites for metastases. When treatment for colorectal cancer liver metastases (CRLM) is intended to be curative, standard of care is surgical resection. An alternative to surgical resection for smaller CRLMs is thermal ablation. We searched for evidence that could be used to answer the question: What is the clinical and cost effectiveness of radiofrequency or microwave ablation to treat small colorectal cancer liver metastases in adults compared to surgical resection in people with ten or fewer CRLMs of 3 cm or less?

Authors' results and conclusions: We identified one randomised controlled trial and five non-randomised cohort studies that used propensity score matching to minimise differences between treatment groups that examined clinical effectiveness of thermal ablation. The evidence included in this review suggests that thermal ablation is non-inferior, or there is no difference, for survival outcomes including overall survival, and progression free survival. People in the thermal ablation group were around 60% less likely to experience an adverse event. Hepatic retreatment may be more common in patients treated with thermal ablation compared to those treated with surgical resection, although reasons for retreatment were uncertain. There was evidence that length of hospital stay was longer for people treated with surgical resection. A cost analysis conducted by HTW found that thermal ablation was expected to be a cost saving treatment option.

Authors' recommendations: The evidence supports the routine adoption of thermal ablation as a treatment option to treat colorectal cancer liver metastases in adults who are eligible for surgical resection.

Authors' methods: The Evidence Appraisal Report is based on a literature search (strategy available on request) for published clinical and economic evidence on the health technology of interest. It is not a full systematic review but aims to identify the best available evidence on the health technology of interest. Researchers critically evaluate and synthesise this evidence. We include the following clinical evidence in order of priority: systematic reviews; randomised trials; non-randomised trials. We only include evidence for “lower priority” evidence where outcomes are not reported by a “higher priority” source. We also search for economic evaluations or original research that can form the basis of an assessment of costs/cost comparison. We carry out various levels of economic evaluation, according to the evidence that is available to inform this.

Authors' identified further research: Further research is recommended to compare quality of life after resection or thermal ablation for CRLM, whether thermal ablation was non-inferior for higher burden disease, and whether evidence collected in high volume centres would be applicable to low volume centres.

Project Status: Completed

Year Published: 2025

URL for published report: https://healthtechnology.wales/reports-guidance/thermal-ablation-of-colorectal-liver-metastases/

English language abstract: An English language summary is available

Publication Type: Rapid Review

Country: Wales, United Kingdom

Organisation Name: Health Technology Wales

Contact Address: c/o Digital Health Care Wales, 21 Cowbridge Road East Cardiff CF11 9AD

Contact Name: Susan Myles, PhD

Contact Email: healthtechnology@wales.nhs.uk