Size of surgical margin does not influence recurrence rates after curative liver resection for colorectal cancer liver metastases

Background: The aim of this study was to examine the relationship between surgical margin status and site of recurrence after potentially curative liver resection for colorectal metastases using an ultrasonic dissection technique. Methods: Between January 2000 and December 2003, 176 patients underwent liver resection with curative intent for colorectal metastases at a single institution. Demographics, operative data, pathological margin status, site of recurrence and long-term survival data were collected prospectively and analysed. Results: On pathological analysis, resection margins were positive in 43 patients, negative by 1-9 mm in 110, and clear by more than 9 mm in 23 patients. At a median follow-up of 33 months, 133 of 176 patients had developed a recurrence, only five of whom had recurrence at the surgical margin. Recurrence at the surgical margin was not significantly related to the size of the margin. Overall, the median time to recurrence was 12.6 months, which was independent of surgical margin size, although there was a significantly higher proportion of patients with multiple metastases in the group with a positive margin (P = 0.008). Margin status did not correlate significantly with either recurrence-free or overall survival. Conclusion: The rate of recurrence at the surgical margin was low and a positive margin was not associated with an increased risk of recurrence either at the surgical margin or elsewhere.