Thermal ablation may improve outcomes in patients with colorectal liver metastasis: a case-control study

Purpose: Local thermal ablation may extend the scope of palliative therapy in patients with colorectal liver metastasis. We performed a retrospective, case-controlled study to compare patients with colorectal liver metastases that were treated with percutaneous radiofrequency (RF) or microwave (MW) thermal ablation, against the control group of chemotherapy alone. Methods: We described baseline demographics, ablation sessions, procedure duration and related complications. We compared outcomes of percutaneous thermal ablation versus chemotherapy alone (controls) in patients with colorectal liver metastasis. The control group assigned (non-ablated patients) had similar demographics and prior treatment profile when compared to ablated patients. Progression free survival (PFS) and overall survival (OS) were estimated for the two groups. Results: Twenty-eight cases with 57 baseline hepatic lesions (median age 68 years; male to female ratio 2:1) were evaluated and compared with 48 controls. A total of 55 sessions (52 RF, 3 MW) were performed among the cases, with minimal procedural time (median 8 min), zero mortality and no severe complications (3 cases of local hepatic hematoma not requiring hospitalization). Ablated patients had prolonged median PFS (19.4 months) and OS (27.5 months) when compared against controls (14.0 and 21.4 months, respectively). After adjusting for hepatic involvement, PFS estimates were comparable and OS was better for the ablated group. One and 2-year survival estimates were 0.96 and 0.79 for thermal ablation patients compared with 0.82 and 0.52 for controls (p=0.05 and p=0.07, respectively). Conclusion: Percutaneous thermal ablation may delay progression and death in colorectal cancer patients with metastatic liver disease.