Objective:To study the safe distal resection margin in low anterior resection with total mesorectal excision for rectal cancer.
Methods:Between January 2003 and December 2007, 412 patients with rectal cancer ≦10 cm from the anal verge underwent low anterior resection with total mesorectal excision, and the rates of pstoperative complications, distal metastasis, tumor recurrence and survival in different distal resection margin lengths were compared.
Results:The rates of post-operative complications and distant metastasis were similar and no significantly differentin in patients with distal margins <2 cm, 2-3 cm or >3 cm. Distal margins <2 cm had significantly higher local recurrence rate (19.30%) when compared with 2-3 cm (8.37%, P=0.015) or >3 cm (7.69%, P=0.029). Kaplan-Meier estimates of survival rates at 3 years for the <2 cm, 2-3 cm and >3 cm groups were 69.4%, 86.5% and 89.9%, respectively, and those at 5years were 63.0%, 70.7% and 71.1%, respectively. Survival was significantly worse when distal margins were <2 cm compared with 2-3 cm (P=0.030) and >3 cm (P=0.040). Survival for the 2-3 cm versus >3 cm groups was not significantly different (P=0.707).
Conclusions:Our data suggest that for patients undergoing low anterior resection with total mesorectal excision for rectal cancer, distal margins less than 2 cm are associated with compromising oncological outcome, and at least 2 cm distal margin seems to be acceptable.