Is a Short Distal Resection Margin of Less than One Centimeter in a Sphincter-saving Resection for Rectal Cancer Oncologically Safe?

Abstract

Purpose: Sphincter preservation is one of the main goals in the treatment of rectal cancer. The aim of this study was to evaluate the oncologic safety of a sphincter-saving resection with a distal resection margin of less than 1 cm. Methods: Two hundred forty-eight patients who underwent a sphincter-saving resection between June 1989 and December 2002 and who had a confirmed distal resection margin of less than 1 cm on pathologic examination were included. All patients were evaluated for local and systemic recurrences. Results: The median follow-up period was 45 (6∼144) months. The mean length of distal resection margin was 0.79±0.26 cm. Lower rectalcancer was most common (56.5%). Forty patients (16.1%) experienced recurrence. The local recurrence rate was 3.6%, systemic recurrence rate was 11.7%, and the combined local and systemic recurrence rate was 0.4%. In systemic recurrence, the liver was the most common site, followed by the lung. Among stage II & III groups, patients who underwent adjuvant chemoradiotherapy experienced significantly lower local recurrence compared to patients in the chemotherapy- only or the no-adjuvant group (2.6%, 12.9%, 8.7%, P=0.05). The length of distal resection margin, the total mesorectal excision, the location of tumor, sex, histology, and stage were not associated with local recurrence. Conclusions: A distal resection margin of less than 1 cm in a sphincter-saving resection showed acceptableoncologic outcomes. Adjuvant chemoradiotherapy were beneficial to reduce local recurrence in the stage II and the stage III groups.