What is a safe distal resection margin in rectal cancer patients treated by low anterior resection without preoperative radiotherapy?

AIM: The aim of this study was to examine what constitutes an acceptable distal resection margin (DRM) when performing sphincter-saving surgery for rectal cancer without preoperative radiotherapy. METHOD: This national study consisted of 3571 patients for whom information on DRM was available and who were radically treated by anterior resection between 1993 and 2004. Of these, 3342 (93.5%) patients had not received preoperative radiotherapy. The DRM was measured on fixed specimens. RESULTS: The 5-year local recurrence rate was 14.5% for patients with a DRM of 0-10 mm compared to 9.6% for patients with a DRM of 11-20 mm, 8.9% for a DRM of 21-30 mm, 7.0% for a DRM of 31-40 mm, 7.7% for a DRM of 41-50 mm and 8.7% for a DRM of > 50 mm. After adjustment for other independent prognostic factors, a DRM of 0-10 mm was found to have significant impact on local recurrence. The DRM had no impact on distant metastases or overall survival. CONCLUSION: For rectal cancer patients treated without radiotherapy, a DRM of > 10 mm is recommended.