BACKGROUND: Gastric cancer patients without invasion of the squamocolumnar junction have a low probability of extragastric mesenteric metastasis, and the survival benefit of conducting D2 lymphadenectomy plus complete mesogastrium excision is unclear in this group of patients. METHODS: This was a retrospective analysis of patients with stage II/III gastric cancer without invasion of the squamocolumnar junction who underwent laparoscopic radical surgery for gastric cancer at the First Hospital of Putian City, Fujian Province, from January 2014 to May 2019. Five-year disease-free survival was the primary outcome, and 5-year overall survival and the recurrence pattern were the secondary outcomes. Morbidity, mortality, and surgery-related outcomes within 30 days of surgery were also analyzed. RESULTS: This study included 366 patients, 133 in the D2 lymphadenectomy group and 233 in the D2 lymphadenectomy plus complete mesogastrium excision group. There was no statistically significant difference in 5-year disease-free survival and overall survival in the D2 lymphadenectomy plus complete mesogastrium excision group compared with the D2 lymphadenectomy group (P >
.05). Regarding recurrence pattern, the D2 lymphadenectomy group had a higher rate of local recurrence (12.3% and 38.3%, P = .001). In subgroup analysis, patients with stage III and T3-4aN1-3 gastric cancer in the D2 lymphadenectomy plus complete mesogastrium excision group had significantly better 5-year disease-free survival compared with the D2 lymphadenectomy group (P <
.05). CONCLUSION: Laparoscopic D2 lymphadenectomy plus complete mesogastrium excision not only decreased the local recurrence rate of stage II/III gastric cancer without invasion of the squamocolumnar junction, but it also improved the 5-year disease-free survival of patients with stage III and T3-4aN1-3 gastric cancer without invasion of the squamocolumnar junction.