Apical lymphadenectomy during low ligation of the IMA during rectosigmoid resection for cancer

Low ligation of the inferior mesenteric artery with preservation of the left colic artery may decrease the risk of colorectal anastomotic ischemia compared to high ligation at its origin. Low ligation leaves apical nodes in situ and is therefore paired with apical lymphadenectomy. We sought to compare relevant oncologic outcomes between high ligation and low ligation plus apical lymphadenectomy in rectosigmoid resection for colorectal cancer.

We conducted a retrospective cohort study. Patients receiving a rectosigmoid resection for cancer between January 2012 and July 2018 were included. Patients with metastatic disease and those who underwent low ligation without apical lymphadenectomy were excluded. Our primary outcome was nodal yield/metastasis. Secondary outcomes included perioperative complications, local recurrence, and overall survival.

Eighty-four patients underwent high ligation and 89 low ligation plus apical lymphadenectomy (median follow-up 20 months). In the low-ligation group, a median of 2 (interquartile range = 1-3) apical nodes was resected; 4.1% were malignant, increasing pathologic stage in 25% of these patients. There were no differences in nodal yield, complications, anastomotic leak, local recurrence, or overall survival.

No differences were identified between high ligation and low ligation plus apical lymphadenectomy with respect to relevant clinical outcomes. Prospective trial data are needed to robustly establish the oncologic benefit and safety of the low ligation plus apical lymphadenectomy technique.