Apical lymph node dissection of the inferior mesenteric artery with preservation of left colic artery in colorectal cancer

Abstract

Background: Nowadays, surgery for colorectal cancer has been standardized both ways in open and laparoscopic approaches but there are still debates regarding the level of ligation of the IMA at its origin from aorta (high ligation) or below the origin of left colic artery (low ligation). The technique of apical lymph node dissection with preservation of LCA has the advantage of both, better lymph node harvest and lower postoperative complications. It is controversial whether a high or low ligation of the inferior mesenteric artery (IMA) is superior. The former allows an extended lymph node clearance whereas the latter preserves the distal vascular supply via the left colic artery (LCA). Apical lymph node dissection of the IMA (ALMA) harvests nodal tissue along the IMA proximal to the LCA whilst performing a low ligation. This anatomically replicates the oncological benefit of high ligation and the vascular preservation of low ligation. This study evaluates the nodal yield of ALMA and the short-term outcome of this technique.Methods: Author retrospectively studied 40 patients with operable sigmoid and rectal cancer who admitted to general surgery department in Menoufia University Hospitals from May 2016 to May 2018. All patient underwent curative surgical resection with ALMA. The lymph node yield from the dissection (the ALMA specimen) was compared with the total lymph node yield. Data on the LCA anatomy, time required to perform ALMA, complications and postoperative recovery were evaluated.Results: Results ALMA was successful in 36 patients. Median postoperative hospitalization was 5 (2-26) days without ALMA-related morbidity or mortality. The median lymph node yield was 20 (9-41) and a median of 14.3 (0-80)% were harvested with ALMA. Two patients not having neoadjuvant chemoradiotherapy had fewer than 12 lymph nodes, excluding nodes harvested from ALMA. The average time required for ALMA was 20min.Conclusions: ALMA (lymph node dissection around the IMA preserving the root of the IMA and LCA) was feasible by this method without compromising operation time, blood loss or the number of harvested lymph nodes with accepted rate of postoperative complications.