Background: Recent reports suggest that a distal clearance (DC) of 10 mm at the lower surgical margin may be considered adequate in the surgical treatment of rectal cancer, but there are no data on the possible adequacy of a < 10-mm DC in N0 patients in whom a good prognosis can otherwise be expected, that is, those with negative surgical margins and negative lymph nodes.
Methods: Between November 1991 and December 1998, 154 consecutive patients with adenocarcinoma of the lower third of the rectum had a total rectal resection with total mesorectal excision and coloendoanal anastomosis. Among 76 N0 patients, there were 35 with <10-mm DC and 41 with > or =10-mm DC. Each group was divided into two subgroups depending on whether the surgical margins were involved or not, and the rate of local recurrence in the various categories was compared. All B2 Astler-Coller stage patients in the series received postsurgical chemoradiotherapy.
Results: The local recurrence rate in the 35 patients with DC < 10 mm was 11.4% and that of the 41 patients with DC > or =10 mm was 7.3%. When only patients with negative surgical margins were considered, the local recurrence rate was 3.4% for those with < 10-mm DC and 5.1% for those with > or =10-mm DC.
Conclusions: Our results suggest that a radical surgery with <10-mm DC followed by chemoradiotherapy may be adequate in N0 patients, provided that a careful pathologic examination of the surgical specimen excludes the presence of lymph node metastases and that the distal rectal and mesorectal resection margins fall in healthy tissue.