Kimura's vs Warshaw's technique for spleen preserving distal pancreatectomy: a systematic review and meta-analysis of high-quality studies

Background: Spleen preserving distal pancreatectomy (SPDP) represents a widely adopted procedure in the presence of benign or low-grade malignant tumors. Splenic vessels preservation and resection (Kimura and Warshaw techniques respectively) represent the two main surgical modalities to avoid splenic resection. Each one is characterized by strengths and drawbacks. The aim of the present study is to systematically review the current high-quality evidence regarding these two techniques and analyze their short-term outcomes.Methods: A systematic review was conducted according to PRISMA, AMSTAR II and MOOSE guide-lines. The primary endpoint was to assess the incidence of splenic infarction and splenic infarction leading to splenectomy. As secondary endpoints, specific intraoperative variables and postoperative complications were explored. Metaregression analysis was conducted to evaluate the effect of general variables on specific outcomes.Results: Seventeen high-quality studies were included in quantitative analysis. A significantly lower risk of splenic infarction for patients undergoing Kimura SPDP (OR = 0.14; p < 0.0001). Similarly, splenic vessel preservation was associated with a reduced risk of gastric varices (OR = 0.1; 95% p < 0.0001). Regarding all secondary outcome variables, no differences between the two techniques were noticed. Metaregression analysis failed to identify independent predictors of splenic infarction, blood loss, and operative time among general variables.Conclusions: Although Kimura and Warshaw SPDP have been demonstrated comparable for most of postoperative outcomes, the former resulted superior compared to the latter in reducing the risk of splenic infarction and gastric varices. For benign pancreatic tumors and low-grade malignancies Kimura SPDP may be preferred.