Adequacy of 1-cm distal margin after restorative rectal cancer resection with sharp mesorectal excision and preoperative combined-modality therapy.

Abstract

Preoperative combined-modality therapy (CMT) for rectal cancer allows a sphincter-sparing procedure in some individuals who would otherwise require an abdominoperineal resection. To further define the subset of rectal cancer patients suitable for this approach, we determined the adequacy of a distal margin of < or = 1 cm in patients with locally advanced rectal cancer requiring preoperative CMT. Ninety-four consecutive patients, status post curative low anterior resection for rectal cancer after preoperative CMT, were identified from the prospective Colorectal Service Database. Distal margin length, tumor grade, tumor-node-metastasis stage, presence of lymphovascular and perineural invasion, and tumor distance from the anal verge were examined for their effect on recurrence and survival. Median follow-up was 44 months. Distal margin length ranged from.1 to 9.5 cm (median, 2.0 cm) and did not correlate with local recurrence (hazard ratio, 1.1; P =.34) or recurrence-free survival (hazard ratio, 1.1; P =.29) by univariate analysis. Kaplan-Meier estimates of recurrence-free survival and local recurrence at 3 years for the < or = 1 cm versus >1 cm and the < ore = 2 cm versus > 2 cm groups were not significantly different. Groups were well matched for other clinicopathologic variables. Our data suggest that for patients with locally advanced rectal cancer undergoing resection and preoperative CMT, distal margins < or = 1 cm do not seem to compromise oncological outcome.