Impact of Spleen Preservation in Patients with Gastric Cancer

Abstract

Background: Resection of the spleen en bloc with the stomach for gastric cancer is still widely performed for a curative resection (R0), but the presence of the spleen may have a favorable effect on recurrence control and survival. The hypothesis that the spleen suppresses tumor growth from minimal residual disease in the critical early postsurgical period and reduces the risk of recurrent disease was tested. Patients and Methods: Patients were included who underwent gastrectomy, with or without splenectomy, for gastric adenocarcinoma. Standardized, strongly-defined criteria were used to accurately stratify patients, who had an extended (D2) lymph node dissection, into the curative and non-curative resection groups. Limited, D1 resection confounds appropriate R-stratification and thus D1 patients were excluded. Prospectively-defined primary endpoints were early (within two years) and overall recurrence and death from any cause and secondary endpoints were postsurgical risks (morbidity, mortality) and metastases to the splenic hilum nodes. Results: Overall survival for the total population studied (n=202) was better for preservation-versus-resection of the spleen among R0 patients (p=0.0001), but not for those with non-curative resection (p=0.42). For the R0 D2 group of patients, preservation (n=59) over resection (n=67) of the spleen, there was no significant difference in in-hospital postoperative morbidity or mortality (3.4% vs. 0%). At a median follow-up of 112 months, significantly the preservation of the spleen, lowered the risks of early recurrence (HR, 0.33; 95% CI, 0.16 to 0.69; p=0.003) and death from any cause (p=0.009) after adjustment analysis. Since at baseline there was a significant imbalance of tumor stage in favor of the spleen-preservation group, we conducted a stage-stratified subgroup analysis. This treatment effect remained consistent in the subgroup analyses according to nodal and serosal status, while in multivariate analysis preservation of the spleen was an independent predictor of outcome. An overestimation of the risk for residual disease in the splenic hilum nodes in the case of spleen preservation was obtained in 94% of splenectomized patients. Conclusion: Our findings indicate that preservation of the spleen may be associated with a reduced risk of early and overall recurrence translated into a better survival in patients receiving curative surgery for gastric cancer. A large randomized trial is needed to confirm this finding. Indications for splenectomy are few, being limited to those patients with advanced proximal cancers.