The value of spleen-preserving lymphadenectomy in total gastrectomy for gastric and esophagogastric junctional adenocarcinomas: A long-term retrospective propensity score match study from a high-volume institution in China

The benefit of removing the splenic lymph nodes in patients with proximal gastric cancer has been controversial. The purpose of our study was to investigate the importance of performing a splenic hilar lymph node dissection without splenectomy in patients undergoing total gastrectomy for gastric cancer.From January 2006 to December 2015, we retrospectively reviewed patients who underwent a curative total gastrectomy for gastric cancer. Propensity score matching was used to balance any potential discrepancy of the other covariates between patients with and without splenic hilar lymph node dissection. Survival analysis, Cox univariate and multivariate analysis, and subgroups analysis were conducted to determine the value of splenic hilar lymph node dissection. After matching, 2 nomograms among patients with and without splenic hilar lymph node dissection were established respectively, the C-index, calibration curve and decision curve analysis were used to further evaluate the value of splenic hilar lymph node dissection.The rate of metastatic splenic hilar lymph nodes in the 274 patients undergoing splenic hilar lymph node dissection was 16.4% (45/274). Patients undergoing splenic hilar lymph node dissection had better survival outcomes than those not undergoing splenic hilar lymph node dissection before (P = .003) and after (P = .003) propensity score matching. Cox multivariate analysis also confirmed that splenic hilar lymph node dissection was an independent prognostic factor both before (hazard ratio 1.284, 95% confidence interval 1.042-1.583, P = .019) and after (hazard ratio 1.480, 95% confidence interval 1.156-1.894, P = .002) propensity score matching. Subgroup analysis indicted that splenic hilar lymph node dissection offered better survival outcomes for esophagogastric junctional adenocarcinoma (P < .001, P for interaction = .018). After propensity score matching, the nomogram of patients with splenic hilar lymph node dissection (C-index 0.735, 95% confidence interval 0.695-0.774) also indicated a statistically significant advantage compared with that without splenic hilar lymph node dissection (C-index 0.708, 95% confidence interval 0.668-0.748, P < .001).Our study suggests that spleen-preserving splenic hilar lymph node dissection should be an essential procedure among patients undergoing total gastrectomy.