Local ablative treatments for liver metastases: the current situation

Surgical resection is the optimal treatment for liver metastases. However, due to their multifocality and/or insufficient remnant liver volume, the majority of liver metastases are unresectable. For this reason, several local ablative techniques have been developed, aiming to produce selective tumour destruction and thus increase the rate of patients amenable to curative-intent treatments. Among these techniques, cryoablation and radiofrequency ablation only have proven to have a curative potential, while transarterial chemoembolization and alcohol injection should be considered as palliative options only. The local recurrences after cryoablation and radiofrequency are equivalent, inferior to 10%, highly dependent of selection criteria. In contrast, morbidity is significantly increased after cryoablation, leading most of the teams to prefer the radiofrequency approach. Two major limitations for radiofrequency are, first, the risk to provoke heat biliary lesion in case of metastases located proximally to hilar plate, and second, the risk of insufficient ablation due to a cooling effect in case of metastases near to major vessels. Keeping in mind these limitations, selective use of radiofrequency may offer a significant benefit by allowing complete tumour clearance in patients with unresectable liver metastases.