A randomized clinical trial comparing the initial vascular approach to the inferior mesenteric vein versus the inferior mesenteric artery in laparoscopic surgery of rectal cancer and sigmoid colon cancer.

BACKGROUND: The inferior mesenteric artery approach with a selective lateral splenic flexure mobilization is the most widely used initial step in laparoscopic rectal and left colon surgery. Surgery started through the inferior mesenteric vein (IMV) with systematic medial mobilization (MM) has some theoretical advantages that have never been analyzed in a clinical trial. The aim of this study was to compare the two techniques with regards to surgical technique variables (conversion, surgical time, bleeding, morbidity, and mortality) and pathological outcomes.

METHODS: A single-blinded, randomized, controlled trial of patients operated electively by laparoscopic with curative intention for rectal or sigmoid cancer was performed at a single, specialized colorectal surgery department from April 2016 to October 2017.

RESULTS: 49 patients were included in each group. There were no statistical differences in patient demographics between the two approaches. Pathological outcomes did not differ between the two groups. Intra-operative characteristics showed a higher conversion rate in patients in which the inferior mesenteric artery was dissected first (p = 0.031). The artery approach also increased intra-operative bleeding (p = 0.049), but there were no differences regarding operative time. On multivariate analysis, the artery approach was associated with a higher risk of conversion (OR 8.68; p = 0.050). Post-operatory complications did not differ between artery and vein dissection.

CONCLUSIONS: In our study, the initial approach by the IMV with a systematic MM of the splenic flexure has allowed us to reduce the conversion rate without increasing complications or the surgical time. No differences were observed in the pathological results. Both approaches seem to be safe and effective and well-trained laparoscopic surgeons should have the two techniques available to them for use as needed.