Survival Benefits and Margin of Liver Metastasectomy in Colorectal Liver Metastasis

Background: Association between resection margin of hepatic resection for colorectal liver metastasis and survival outcome remains controversial. While a margin of 10mm had been the traditional standard, several studies had been published in the past with conflicting results. Method: This is a retrospective review of 385 patients who underwent liver resection for colorectal liver metastasis in a single centre from 2000-2017. Survival data were correlated with demographics, liver resection margin, KRAS status, CEA levels and analysed for statistical significance using long-rank test and cox regression with multivariate analysis. Result: There is statistically significant association between the width of liver resection margin and both overall and disease free survival. Microscopic margin of greater than 10 mm is associated with significant benefit in both disease free (9.8 vs 15.8 months P=0.001) & overall survival (43.9 vs 58.9 months P= 0.012). Cutoff for free resection margin beyond 14mm did not correlate with significant difference in survival. The other factors associated with survival benefits was CEA less than 5 on admission (95%CI 0.53-0.92 p=0.01). Conclusion: Liver resection margin of greater than 1mm is an independent predictor of increased disease free survival. There is clinically and statistically significant improved survival if liver resection margin of greater than 10mm can be achieved.