LAUSR

Background Numerous studies have shown that the short-term efficacy of three-dimensional (3D) laparoscopic radical gastrectomy (LG) is comparable to that of two-dimensional (2D)-LG. Whether 3D-LG affects the recurrence patterns of gastric cancer (GC) patients has not been investigated. Methods From January 2015 to April 2016, a total of 419 patients were recruited for a phase III clinical trial (NCT02327481), which compared the short-term outcomes between the 2D and 3D groups. The long-term efficacy including recurrence patterns was compared between the 2D and 3D groups in this retrospective study. Multivariate analyses were performed to determine whether 3D-LG affects the recurrence patterns. Results Ultimately, 401 patients were analyzed (197 in the 2D-LG group and 204 in the 3D-LG group), and no differences were observed in the clinicopathological data between the two groups. There were no significant differences between the two groups in the recurrence types, first recurrence time or recurrence-free survival (RFS) (all p  > 0.05). According to the 7th American Joint Committee on Cancer tumor-node-metastasis (TNM) staging system, both groups were stratified into pathological stages I, II, and III. The stratified analysis showed no significant differences in RFS or overall survival (OS) among patients in each subgroup (all p  > 0.05). The multivariate analysis of RFS showed that tumor diameter, pTNM stage, lymphovascular invasion, and adjuvant chemotherapy were independent factors (all p  < 0.05). The multivariate analysis of post-recurrence survival (PRS) showed that adjuvant chemotherapy was an independent protective factor ( p  = 0.043). Conclusions 3D-LG for GC did not differ significantly from 2D-LG in the effects on 3-year recurrence patterns, RFS and OS, which provides more tumor-related evidence for 3D technology. And due to the technological similarity, it may have certain reference value for robotic-assisted gastrectomy. Further multicenter, large-scale clinical trials are warranted.