Prior hepatectomy predicts local tumor progression and survival after percutaneous ablation of colorectal liver metastasis

Abstract

Background: We hypothesized that the currently utilized hepatic resection criteria for patients with colorectal liver metastasis (CLM) promotes selection of patients with optimal tumor biology translated in low rates of local tumor progression (LTP) at post-resection developed CLM treated with percutaneous ablation (PA). Methods: 82 consecutive patients with 97 CLMs treated with PA during 2004-2014 were included. Local tumor progression-free survival (LTPFS) at the ablated lesions between patients with (n=49) and without (n=33) prior hepatic resection were analyzed. Multivariate Cox regression analysis was utilized to identify factors associated with LTPFS. Results: Median follow-up period was 28 months. 3-year actuarial LTPFS at the ablated lesions was better in patients with prior hepatic resection when compared to patients without prior hepatic resection (73% vs 34%, P<0.001). 3-year recurrence-free survival (RFS) (23% vs 9.1%, P=0.02) and overall survival (OS) (78% vs 48%, P=0.003) were better on patients with prior hepatic resection. Negative predictors for LTPFS on multivariate analysis were: no prior hepatic resection (hazard ratio [HR] 2.35, 95% confidence interval [CI] 1.02-5.45; P=0.045), minimal ablation margin < 5 mm (HR 2.4, 95% CI 1.18-4.87; P=0.016), and RAS mutant (HR 2.65, 95% CI 1.18-5.94; P=0.019). Conclusion: Prior hepatic resection is associated with improved LTPFS, RFS, and OS after PA of CLMs. This suggests inherent differences in tumor biology among surgical and non-surgical populations.