Effect of subcentimeter nonpositive resection margin on hepatic recurrence in patients undergoing hepatectomy for colorectal liver metastases. Evidences from 663 liver resections

Objective: To elucidate if a nonpositive <1-cm resection margin has any effect on hepatic recurrence in patients undergoing liver resection for colorectal liver metastases.Patients and methods: Six hundred and nine patients underwent 663 liver resections. Patients with positive margin were excluded from the analysis. Two groups were studied: group A, <1-cm resection margin and group B, ≥1-cm resection margin.Results: A total of 545 liver resections in 523 patients were carried out with nonpositive resection margins. With a median follow-up of 25 months, the 5-year cumulative hepatic recurrence reached 54% in group A (n = 206) and 41% in group B (n = 339). Factors associated with hepatic recurrence were synchronic metastases (P = 0.0015), bilobar (P < 0.001), two or more metastases (P < 0.001), margin <1 cm (P = 0.0123) and extrahepatic disease (P = 0.0037). A strong correlation between resection margin and number of metastases was confirmed (P < 0.001). At multivariate analysis only two factors were independent predictors of hepatic recurrence: multinodular disease in the liver specimen [≥4 metastases hazard ratio (HR) = 3.45; 95% confidence interval (CI): 2.2-5.38; P < 0.001] and extrahepatic disease at hepatectomy (HR = 1.58; 95% CI: 1.58-3.32).Conclusion: Subcentimeter nonpositive resection margins do not directly influence hepatic recurrence in patients undergoing hepatectomy for colorectal liver metastases.