The effectiveness and safety of D2 plus para-aortic lymphadenectomy for resectable gastric cancer: a systematic review and meta-analysis

Background: Gastric cancer (GC) is among the malignant tumors of highest morbidity and mortality in the world, and has a profile of high lymph node metastasis rate. Lymph node clearance is a critical part of gastric cancer surgery, however, the extent of lymph node clearance, for example, whether to perform abdominal aortic lymph node dissection, remains considerably controversial. In this study, we performed a systematic review and meta-analysis to assess the effects of D2 plus para-aortic lymphadenectomy (PALD) on survival and postoperative complications in patients with GC. Methods: An electronic search was conducted through PubMed, Embase and cochrane library. The Q test and I 2 were used to assess heterogeneity. The publication bias was evaluated via funnel plots. All statistical analyses were performed using STATA 14.0 (STATA, College Station, TX). Results: 908 studies were retrieved via literature search and eight studies were finally included. There was no significant difference between D2 and D2+PALD in the 5-year survival rate after surgery (HR: 1.00, 95% CI: 0.97-1.03, P = 0.897; I 2 = 64.9%). Besides, the 30-day mortality (RR: 1.17, 95% CI: 0.66-2.10, P = 0.590; I 2 = 0.0%) and the overall risk of postoperative complications (RR: 1.15, 95% CI: 0.83-1.59, P = 0.411; I 2 = 35.5%) were comparable between D2 and D2+PALD. Conclusion: Based on current literature body, compared with D2, D2+PALD does not prevail in terms of long-term survival or perioperative outcomes.