Complete Mesocolic Excision Compared With Conventional Right Hemicolectomy for Colorectal Cancer Outcomes: A Systematic Review and Meta-Analysis of Observational Cohorts

This systematic review and meta-analysis was conducted to assess the results of complete mesocolic excision (CME) versus the traditional right hemicolectomy to treat right colon cancer. The major purpose was to determine variations with respect to lymph node yield, survival, morbidity, mortality, and the time and length of hospital stay. In accordance with Preferred Reporting Items of Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a literature search was implemented using PubMed, Scopus, Web of Science, and CINAHL databases to identify observational cohort studies published between January 2015 and June 2025. Studies were included in the review if they were published in English and contained comparative data. In total, six observational studies were included with approximately 710 participants. Two reviewers completed data extraction, and a random-effects model was used to conduct the analysis. The overall mean variation in the number of locations of lymph nodes was in favor of CME. The CME group had an average time that was an estimated 22 minutes longer. The two groups were not significantly different in terms of postoperative morbidity and mortality. The trend of superiority shown by CME in pooled five-year overall survival and disease-free survival was not statistically significant. The level of risk of bias, as measured using the Newcastle-Ottawa Scale, was low to moderate, and funnel plots did not suggest the presence of significant publication bias. These results indicate that CME can provide an oncologic benefit without affecting safety. However, additional large-scale prospective studies, which are methodologically sound, are needed to verify these observations.