Complete Mesocolic Excision and D3 Lymphadenectomy versus Conventional Colectomy for Colon Cancer: A Systematic Review and Meta-Analysis.

Previous systematic reviews suggest that the implementation of ‘complete mesocolon excision’ (CME) for colon tumors entails better specimen quality but with limited long-term outcomes. We performed a meta-analysis to compare the pathological, perioperative, and oncological results of CME with conventional surgery (CS) in primary colon cancer. Embase, MEDLINE and CENTRAL databases were searched using Medical Subject Headings for CME and D3 lymphadenectomy. The systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A total of 18,989 patients from 27 studies were included. Postoperative complications were higher in the CME group (relative risk [RR] 1.13, 95% confidence interval [CI] 1.04–1.22, I2 = 0%), while no differences were observed in terms of anastomotic leak (I2 = 0%) or perioperative mortality (I2 = 49%). CME was associated with a higher number of lymph nodes harvested (I2 = 95%), distance to high tie (I2 = 65%), bowel length (I2 = 0%), and mesentery area (I2 = 95%). CME also had positive effects on 3- and 5-year overall survival (RR 1.09, 95% CI 1.04–1.15, I2 = 88%; and RR 1.05, 95% CI 1.02–1.08, I2 = 62%, respectively) and 3-year disease-free survival (RR 1.10, 95% CI 1.04–1.17, I2 = 22%), as well as decreased local (RR 0.35, 95% CI 0.24–0.51, I2 = 51%) and distant recurrences (RR 0.71, 95% CI 0.60–0.85, I2 = 34%). Limited evidence suggests that CME improves oncological outcomes with a higher postoperative adverse events rate but no increase in anastomotic leak rate or perioperative mortality, compared with CS.