The influence of the distal resection margin length on local recurrence and long-term survival in patients with rectal cancer after chemoradiotherapy and sphincter- preserving rectal resection

Background. Low recurrence rates and long term survival are the main therapeutic goals of rectal cancer surgery. Complete, margin-negative resection confers the greatest chance for a cure. The aim of our study was to determine whether the length of the distal resection margin was associated with local recurrence rate and long-term survival. Patients and methods. One hundred and nine patients, who underwent sphincter-preserving resection for locally advanced rectal cancer after preoperative chemoradiotherapy between 2006 and 2010 in two tertiary referral centres were included in the study. Distal resection margin lengths were measured on formalin-fixed, pinned specimens. Characteristics of patients with distal resection margin < 8 mm (Group I, n = 27), 8-20 mm (Group II, n = 31) and > 20 mm (Group III, n = 51) were retrospectively analysed and compared. Median (range) follow-up time in Group I was 89 (51-111), in Group II 83 (57-111) and in Group III 80 (45-116) months (p = 0.326), respectively. Results. Univariate survival analysis showed that distal resection margin length was not statistically significantly associated with overall survival or local recurrence rate (p > 0.05). In a multiple Cox regression analysis, after adjusting for pathologic T and N stage (yT, yN), distal resection margin length was still not statistically significantly associated with overall survival. Conclusions. Our study shows that close distal resection margins can be accepted as oncologically safe for sphincter-preserving rectal resections after preoperative chemoradiotherapy.