Can thermal ablation be used to treat colorectal liver metastases safely?
Thermal ablation uses heat (radiofrequency or microwave) to destroy tumors. For colorectal cancer that has spread to the liver, thermal ablation is a well-studied option, especially for small tumors (≤3 cm). Research shows it is safe, with a very low risk of serious complications and death. For selected patients, it offers similar long-term survival to surgical resection, with fewer side effects and faster recovery.
What the research says
A large 2025 randomized trial (COLLISION) compared thermal ablation to surgical resection in patients with up to 10 small colorectal liver metastases (≤3 cm). The study found that thermal ablation was non-inferior to surgery for overall survival, meaning it was not worse than surgery. The trial also reported fewer complications and shorter hospital stays with ablation 6. This confirms earlier findings that thermal ablation is a safe alternative for small, resectable liver metastases 7.
A systematic review of minimally invasive surgical thermal ablation (MITA) including 3983 patients found a major complication rate of only 2.2% and a 30-day mortality of 0.25%. For colorectal liver metastases specifically, 5-year overall survival was 43% and disease-free survival was 43% 4. These numbers are comparable to outcomes after surgical resection.
Another meta-analysis of robotic simultaneous resection for colorectal cancer and liver metastases showed that combining surgery for the primary tumor and liver metastases in one operation is feasible and safe, with low conversion rates and a 30-day mortality of 0.9% 3. While this study focused on robotic surgery, it supports the overall safety of minimally invasive approaches for liver metastases.
It is important to note that not all patients with liver metastases are candidates for ablation. For example, a phase II trial found no survival benefit for liver resection in patients who also had unresectable lung metastases 5. Therefore, patient selection is key.
What to ask your doctor
- Is my liver metastasis small enough (≤3 cm) and in a good location for thermal ablation?
- What are the risks of thermal ablation compared to surgery for my specific case?
- How does thermal ablation affect my overall treatment plan, including chemotherapy?
- What is the expected recovery time and hospital stay with ablation versus surgery?
- Are there any long-term follow-up scans needed after ablation to check for recurrence?
This question is drawn from common patient questions about Oncology and answered using cited medical research. We do not provide individualized advice.