INFLUENCE OF RESECTION MARGIN ON SURVIVAL AND LIVER RECURRENCE FOLLOWING RESECTION FOR COLORECTAL LIVER METASTASES.

Introduction Recent studies have questioned the role of a positive resection margin (R1) as prognostic factor in hepatic resections of colorectal liver metastasis (CLM). The aim of this study was to evaluate the pattern of relapse and the impact of R1 resections on survival. Methods We retrospectively collected clinicopathological and follow-up data from 89 consecutive patients submitted to liver resection for CLM. R0 was defined by the absence of microscopic tumor’s invasion of the resection margin. In patients with multiple metastasis the closest margin was taken as representative. Relapse free survival (RFS) and overall survival (OS) were calculated from the time of liver resection, respectively, to the first relapse and to the last follow-up or death. Survival and recurrence according to R1 and R0 resection were analysed with Kaplan-Meier and compared with Log-rank test. Results At a median follow-up of 30.0 months recurrence occurred in 70.8% of patients. Liver recurrence was present in 50% of cases. The median RFS was 16.10 months (CI= 9.24-22.96) and OS was 45.3 months (CI=25.51-65.15). The R1 resection margin rate was 21.3% (n=19). Five years OS rate was significantly lower in R1 resection (Log-Rank Test=0.0125). R1 resection was not significantly correlated with liver recurrence (p=0.547) and time of recurrence (Log-Rank Test=0.09). Metastasis size major than 30 mm was associated with lower incidence of R1 resections (p=0.04). Conclusions With the limits of a retrospective analysis and a relatively small number of patients in our study R1 resections seems to influence Overall Survival but does not correlate with liver recurrence and Relapse Free Survival.