Persistent descending mesocolon as a vital risk factor for anastomotic failure and prolonged operative time for sigmoid colon and rectal cancers

Abstract

Background The diagnostic criteria and effect of persistent descending mesocolon (PDM) on sigmoid and rectal cancers (SRCs) remain controversial. This study aims to clarify PDM patients' radiological features and short-term surgical results. Method From January 2020 to December 2021, radiological imaging data from 845 consecutive patients were retrospectively analyzed using multiplanar reconstruction (MRP) and maximum intensity projection (MIP). PDM is defined as the condition wherein the right margin of the descending colon is located medially to the left renal hilum. Propensity score matching (PSM) was used to minimize database bias. The anatomical features and surgical results of PDM patients were compared with those of non-PDM patients. Results Thirty-two patients with PDM and 813 patients with non-PDM were enrolled into the study who underwent laparoscopic resection. After 1:4 matching, patients were stratified into PDM (n = 27) and non-PDM (n = 105) groups. The lengths from the inferior mesenteric artery (IMA) to the inferior mesenteric vein (1.6 cm vs. 2.5 cm, p = 0.001), IMA to marginal artery arch (2.7 cm vs. 8.4 cm, p = 0.001), and IMA to the colon (3.3 cm vs. 10.2 cm, p = 0.001) were significantly shorter in the PDM group than those in the non-PDM group. The conversion to open surgery (11.1% vs. 0.9%, p = 0.008), operative time (210 min vs. 163 min, p = 0.001), intraoperative blood loss (50 ml vs. 30 ml, p = 0.002), marginal arch injury (14.8% vs. 0.9%, p = 0.006), splenic flexure free (22.2% vs. 3.8%, p = 0.005), Hartmann procedure (18.5% vs. 0.0%, p < 0.001) and anastomosis failure (18.5% vs. 0.9%, p = 0.001) were significantly higher in the PDM group. Moreover, PDM was an independent risk factor for prolonged operative time (OR = 3.205, p = 0.004) and anastomotic failure (OR = 7.601, p = 0.003). Conclusion PDM was an independent risk factor for prolonged operative time and anastomotic failure in SRCs surgery. Preoperative radiological evaluation using MRP and MIP can help surgeons better handle this rare congenital variant.

Transverse Colon Volvulus Secondary to the Persistent Descending Mesocolon: A Case Report

“…This contributes to a higher incidence of marginal vascular arch injuries and weaker blood supply at the proximal end of the. Despite our patient being an 18-year-old adolescent, the measured distances (21 mm and 24 mm) were shorter than reported averages (27 mm and 35 mm) [6], likely contributing to her postoperative stenosis, requiring reoperation. The potential use of intraoperative indocyanine green (ICG) to ensure adequate blood supply during the operation is emphasized.…”

“…PDM is confirmed when the descending colon is located medially to the left renal hilum [ 4 ]. Although often asymptomatic, recent studies have identified specific complications associated with PDM, including primary colonic varices [ 14 ], sigmoid colon volvulus [ 15 ], prolonged operative time, anastomotic failure [ 6 ], and postoperative anastomotic stenosis in left-sided colon cancer [ 16 ]. The increased risk of anastomotic failure in PDM cases is linked to the incompletely expanded mesentery of the descending and sigmoid colon, resulting in a shorter length between the inferior mesenteric artery (IMA) and the marginal artery and colon.…”

“…While many cases remain asymptomatic, certain clinical complications, such as sigmoid colon volvulus and intestinal obstruction, have been documented [ 5 ]. Notably, recent studies have identified PDM as an independent risk factor for prolonged operative times and anastomotic failures in sigmoid and rectal cancer surgeries [ 6 ], gradually gaining recognition for its clinical significance.…”

The Atlas of the Inferior Mesenteric Artery and Vein under Maximum-Intensity Projection and Three-Dimensional Reconstruction View

“…In most PDM cases, LCAs were far from the IMA root or absent. If surgeons are not aware of the anatomical variants of the colonic vessels before surgery, they may easily mistake the marginal vessels for the LCA and injure them during surgery, resulting in ischemia of the descending colon or even an unexpected colostomy [30].…”