High versus low ligation of the inferior mesenteric artery during laparoscopic rectal cancer surgery: A prospective study of surgical and oncological outcomes.

Background And Objectives: There is controversy regarding whether the inferior mesenteric artery (IMA) should be ligated at its origin from the aorta (high ligation, HL) or below the branch of the left colic artery (low ligation, LL) during surgery for rectal cancer.

Methods: This prospective study randomized 95 patients with histologically proven rectal cancer (clinical stages I-III based on the 8th American Joint Committee on Cancer guidelines) to undergo HL (n = 47) or LL with lymph node dissection at the root of the IMA (n = 48).

Results: Only two intraoperative adverse events were observed (two HL patients experienced anastomotic ischemia and underwent extended bowel excision and splenic flexure mobilization). The LL group had a significantly shorter time to first flatus (p < .0001). No significant differences were observed in operative time (p = .14), intraoperative blood loss (p = .21), distance from the upper margin (p = .77), distance from the lower margin (p = .35), harvested lymph nodes (p = .33), or anastomotic leakage (p = .44), 2-year overall survival (p = .97), or 2-year disease-free survival (p = .42).

Conclusion: During laparoscopic low anterior resection, a combination of LL at the IMA and vascular root lymph node dissection may help protect the blood supply of the anastomosis, reduce postoperative complications, and enhance recovery, without compromising radical excision.