Therapeutic efficacy of combined intraoperative ablation and resection for colorectal liver metastases: An international, multi-institutional analysis

Background: Only 10-25% of patients presenting with colorectal liver metastases (CRLM) are amenable to hepatic resection. By combining resection and ablation, the number of patients eligible for surgery can be expanded. We sought to determine the efficacy of combined resection and ablation for CRLM. Methods: Between 1984 and 2009, 1,425 patients who underwent surgery for CRLM were queried from an international multi-institutional database. Of these, 125 patients underwent resection combined with ablation as the primary mode of treatment. Results: Patients presented with a median of six lesions. The median number of lesions resected was 4; the median number of lesions ablated was 1. At last follow-up, 84 patients (67%) recurred with a median disease-free interval of 15 months. While total number of lesions treated (hazard ratio (HR)=1.47, p=0.23) and number of lesions resected (HR=1.18, p=0.43) did not impact risk of intrahepatic recurrence, the number of lesions ablated did (HR=1.36, p=0.05). Overall 5-year survival was 30%. Survival was not influenced by the number of lesions resected or ablated (both p>0.05). Conclusion: Combined resection and ablation is associated with long-term-survival in a subset of patients; however, recurrence is common. The number of lesions ablated increases risk of intrahepatic recurrence but does not impact overall survival.