Laparoscopic Complete Mesocolic Excision Versus Noncomplete Mesocolic Excision: A Systematic Review and Meta-analysis

Background: Complete mesocolic excision (CME) emphasizes sharp dissection along the mesocolon plane and ligation of the supplying vessels at their origin. Although laparoscopic CME is reported to be feasible and safe, the benefit of laparoscopic CME over noncomplete mesocolic excision (NCME) remains unclear. This meta-analysis aimed to compare the safety, quality, and effect of laparoscopic CME with NCME. Materials and Methods: A systematic literature search with no limits was performed in PubMed, Embase, and Web of Science on March 27, 2020. Studies comparing laparoscopic CME with NCME were enrolled. Outcomes of interests included intraoperative, pathologic, postoperative, and survival outcomes. Results: Seven studies (5 articles and 2 conference abstracts) published between 2015 and 2020 with a total of 1595 patients (742 by CME and 853 by NCME) were enrolled. Compared with NCME, laparoscopic CME was associated with less intraoperative blood loss [P<0.001, weighted mean difference (WMD)=-12.01, 95% confidence interval (CI): -13.56 to -10.45, I-2=44%], more harvested lymph nodes (P<0.001, WMD=6.50, 95% CI: 3.57-9.42, I-2=89%), longer length of specimens (P=0.004, WMD=3.57, 95% CI: 1.12-6.03, I-2=93%), longer distance from tumor to high tie (P<0.001, WMD=1.36, 95% CI: 0.87-1.85, I-2=76%), and longer distance from nearest bowel wall to high tie (P<0.001, WMD=1.36, 95% CI: 0.87-1.85, I-2=85%). No differences were observed in terms of operative time, postoperative complications, wound infection, ileus, proximal, and distal resection margin or disease-free survival between 2 groups. Conclusions: The currently limited evidences suggest that laparoscopic CME can slightly decrease intraoperative blood loss and improve specimen quality, but its safety and survival benefits need to be further studied. High-quality evidences are needed before laparoscopic CME can be recommended as the standard procedure for colon cancer surgery.