Aim: To investigate oncologic efficacy of prophylactic laparoscopic superior mesenteric vein (No. 14v) lymph node (LN) dissection for lower-third gastric cancer (LTGC).
Methods: We retrospectively collected data from 757 patients who underwent laparoscopic-assisted distal gastrectomy for LTGC. Of these patients, 102 underwent 14v LN dissection (14vD+ group), and the remaining 655 patients did not undergo 14v LN dissection (14vD- group). The outcomes were compared using a 1:1 propensity score matching method.
Results: After matching, 93 patients from the 14vD+ group and 93 patients from the 14vD- group with similar clinicopathological characteristics were compared. Before matching, the overall survival (OS) was similar between the two groups (P = 0.742). After matching, the OS was greater in the 14vD+ group (P = 0.025). The status of 14v dissection was not a significant prognostic factor in the survival analyses, both before and after matching. However, a stratified analysis according to the independent factors in the OS showed that the OS in the 14vD+ group was higher than that in the 14vD- group for cT2-3 patients after matching. The forest plot of OS showed that after matching the 14vD+ group had a significantly higher 3-year OS rate than the 14vD- group in cT2-3 patients. The distribution of the therapeutic index demonstrated that the index of 14v LN was similar to those of Nos. 1, 7, 8a, 9, and 11p after matching.
Conclusions: Adding laparoscopic 14v dissection for laparoscopic-assisted radical distal gastrectomy was safe and might improve the OS for clinically advanced LTGC without serosal invasion.
Keywords: Gastric carcinoma; Lymphadenectomy; No. 14v lymph node; Prognosis; Propensity score matching.