Randomized Controlled Trial to Evaluate Splenectomy in Total Gastrectomy for Proximal Gastric Carcinoma

Objective: To clarify the role of splenectomy in total gastrectomy for proximal gastric cancer. Backgrounds: Splenectomy in total gastrectomy is associated with increased operative morbidity and mortality, but its survival benefit is unclear. Previous randomized controlled trials were underpowered and inconclusive. Methods: We conducted a multiinstitutional randomized controlled trial. Proximal gastric adenocarcinoma of T2-4/N0-2/M0 not invading the greater curvature was eligible. During the operation, surgeons confirmed that R0 resection was possible with negative lavage cytology, and patients were randomly assigned to either splenectomy or spleen preservation. The primary endpoint was overall survival (OS) and the secondary endpoints were relapse-free survival, operative morbidity, operation time, and blood loss. The trial was designed to confirm noninferiority of spleen preservation to splenectomy in OS with a noninferiority margin of the hazard ratio as 1.21 and 1-sided alpha of 5%. Results: Between June 2002 and March 2009, 505 patients (254 splenectomy, 251 spleen preservation) were enrolled from 36 institutions. Splenectomy was associated with higher morbidity and larger blood loss, but the operation time was similar. The 5-year survivals were 75.1% and 76.4% in the splenectomy and spleen preservation groups, respectively. The hazard ratio was 0.88 (90.7%, confidence interval 0.67-1.16) (<1.21); thus, the noninferiority of spleen preservation was confirmed (P = 0.025). Conclusions: In total gastrectomy for proximal gastric cancer that does not invade the greater curvature, splenectomy should be avoided as it increases operative morbidity without improving survival.