D3 Versus D2 Lymphadenectomy in Right Hemicolectomy: A Systematic Review and Meta-analysis

Purpose D3 lymphadenectomy for right colon cancer improves oncological outcomes. This meta-analysis aimed to compare operation data, histopathological characteristics, perioperative conditions, and long-term survival after D3 and D2 lymphadenectomy in right hemicolectomy. Methods We searched PubMed, Embase, and the Cochrane Library for relevant articles (up to March 31, 2020). Random-effects and fixed-effects meta-analysis models were used. Review Manager (RevMan) version 5.3 and Stata version 15.1 were used for pooled estimates. Results After screening 714 articles, 7 articles with a total of 1368 patients were eligible for inclusion. Compared with D2, D3 lymphadenectomy improves results in terms of blood loss (weighted mean difference [WMD] = -20.63, 95% confidence interval [CI] -28.19 to -13.16, P < .01), harvested lymph nodes (WMD = 8.86, 95% CI 7.74 to 9.98, P < .01), 3-year overall survival (OS) (hazard ratio [HR] = 2.03, 95% CI 1.20 to 3.43, P < .01), 5-year OS (HR = 2.22, 95% CI 1.15 to 4.30, P = .02), and 5-year disease-free survival (DFS) (HR = 2.16, 95% CI 1.19 to 3.90, P = .01). There was no significant difference regarding operation time, anastomosis leakage, wound infection, overall morbidity, postoperative hospital stay, mortality, length of dissected colon, and 3-year DFS (P >= .05). Conclusions It is suggested in this review that D3 lymphadenectomy is superior to D2 lymphadenectomy in terms of blood loss, harvested lymph nodes, 3-year OS, 5-year OS, and 5-year DFS. The conclusion must be drawn with caution due to the limited number of included studies. Further RCTs are needed for stronger evidence.

Automated summary

This meta-analysis aimed to compare the outcomes of D3 and D2 lymphadenectomy in right hemicolectomy for right colon cancer. The results showed that D3 lymphadenectomy was superior to D2 lymphadenectomy in terms of blood loss, harvested lymph nodes, 3-year overall survival, 5-year overall survival, and 5-year disease-free survival. Further randomized controlled trials are needed for stronger evidence.