Level of arterial ligation in sigmoid colon and rectal cancer surgery.

Abstract

358 Background: Curative resection of sigmoid colon and rectal cancer includes "high tie" of the inferior mesenteric artery (IMA). However, IMA ligation compromises blood flow to the anastomosis, which may increase the leakage rate and it is unclear whether this confers a survival advantage. Accodingly, IMA may be ligated at a point just below the origin of the left colic artery (LCA) ("low tie"), with lymph node (LN) dissection around IMA. No study has investigated the detailed prognostic results between "high tie" and "low tie, with LN dissection around IMA". The aim of this study was to assess the utility of "low tie, with LN dissection around IMA" on survival in patients with sigmoid colon or rectal cancer. Methods: A total of 268 sigmoid colon or rectal cancer patients who underwent curative operation from 1998 to 2007 were enrolled in this study. The patient's medical records were reviewed to obtain information about operative method, the number of LN dissection, the number of metastatic LN, the site of metastatic LN, recurrence pattern, complication. Overall survival and relapse-free survival were calculated using the Kaplan-Meier method, with differences assessed using logrank test. Results: We divided all patients into three groups according to the ligation level of IMA. 41 patients were ligated at the level of IMA root (Group A: "high tie"). 164 patients were ligated just caudally to the origin of the LCA ("low tie"), with LN dissection around IMA. 63 patients were ligated at the level of superior rectal artery just caudally to the sigmoid artery. The significant difference was not observed in a complication rate in three groups. The significant difference was not observed in the survival rate and the relapse-free survival rate according to each stage in group A and group B either. Also, the significant difference was not observed in the survival rate and the relapse-free survival rate in node-positive cases in group A and group B. Conclusions: "Low tie,with lymph node dissection aroud IMA" is anatomically less invasive and is not inferior to the ligation in the IMA root ("hige tie") in prognostic point.