High Ligation of the Inferior Mesenteric Artery in Left-Sided Colon and Rectal Cancer Resection: Rates of Success and Outcomes

Background High ligation of the inferior mesenteric artery, defined as ligation before the takeoff of the left colic artery, is often described as the gold standard in low left-sided colon and rectal cancer surgery. The aim of this study is to quantify the rate of ligation at the described level at a single academic center. Additionally, we examined the relationship between level of ligation and cancer-related outcomes.Methods This retrospective cohort study included patients ages 18 and over with low left-sided colon, rectal, and anal cancers undergoing surgical resection. Radiographic evidence of high ligation was defined as ligation of the inferior mesenteric artery before the takeoff of the left colic artery. Patients with and without radiographic evidence of high ligation on CT were compared. Secondary outcomes include lymph node yield and positivity, need for adjuvant therapy, and time from surgery to adjuvant therapy.Results 169 patients (54% male) were included in the study. 61.5% of operative reports described high ligation of the IMA. There was radiographic evidence of high ligation in 55.6% of total patients and in 70.2% of patients where high ligation was intended. There was no significant difference in surgeon experience, surgical procedure, or surgical approach. There was no difference in lymph node yield, time to adjuvant chemotherapy, or recurrence rates.Conclusion This study demonstrates good technical success rate of high ligation of the inferior mesenteric artery but shows no difference in short-term patient-measured outcomes between high and low ligation (or successful and unsuccessful high ligation).