Laparoscopic Versus Open Thermal Ablation of Colorectal Liver Metastases: A Propensity Score-Based Analysis of Local Control of the Ablated Tumors.

Background: Laparoscopic ablation (LA) of colorectal liver metastases (CRLMs) is frequently performed in combination with laparoscopic liver resection or as a stand-alone procedure. However, LA is technically demanding and whether the results are comparable with those of open ablation (OA) has not been determined to date. This study compared the effectiveness of LA and OA in achieving local tumor control of CRLMs.
Methods: Patients undergoing LA or OA of CRLMs at Ghent University Hospital between June 2007 and February 2018 were identified from a prospective database. Lesions treated by LA and OA were matched 1:1 using a propensity score based on lesions (liver segment, size, deepness, proximity to a vessel), patients, and procedural characteristics. Ablation sites were followed up with computed-tomography or magnetic resonance imaging to assess the completeness of the ablation and ablation-site recurrence (ASR). Analysis of ASR was performed with the Kaplan-Meier method and Cox regression.
Results: In this study, 163 patients underwent the surgical ablation (78 LA, 85 OA) of 333 CRLMs (143 LA, 190 OA). After matching, 220 lesions (110 LA, 110 OA) were analyzed. Ablation was complete in 93.7% (LA) and 97.3% (OA) of the sites (p = 0.195). No difference in ASR was observed (p = 0.351), with a cumulative risk of ASR at 12 months of 9.1% (LA) and 8.2% (OA). After multivariable analysis, ASR was confirmed to be independent of the surgical approach.
Conclusion: The findings showed that LA and OA achieve a comparable local control of CRLMs. This result further supports the adoption of a laparoscopic approach for the treatment of CRLMs.