A commentary on “Splenic vessels preserving versus Warshaw technique in spleen preserving distal pancreatectomy: A systematic review and meta-analysis” (Int J Surg 2022;103:106686)

Abstract

Dear Editor, Distal pancreatectomy (DP) with concomitant splenectomy is a widely accepted and practiced surgical procedure for tumors located in the body and tail of pancreas. Owing to the increasing awareness of the hematological and immunological roles of the spleen as well as the various complications associated with splenectomy, surgeons prefer spleen-preserving DPs for benign or low-grade malignant pancreatic tumors [1,2]. Spleen preservation can be performed either via splenic vessels preservation (SVP) [3] or the Warshaw technique (WT) [4]. The latter operation involves ligation of splenic vessels while preserving short gastric and left gastroepiploic vessels to ensure blood supply to the spleen. Several studies conducted to evaluate the clinical efficacy of these two surgical techniques revealed inconsistent results [5,6]. We read with great interest the article titled “Splenic vessels preserving versus Warshaw technique in spleen preserving distal pancreatectomy: A systematic review and meta-analysis” by Hang et al. [7]. The authors concluded that both the surgical approaches were safe and effective but SVP-DP was associated with fewer splenic infarcts and gastric varices than WT. In the current study, the authors included 20 studies and performed a comprehensive analysis of several perioperative clinical indicators, including splenic infarction, gastric varices, major complications, postoperative pancreatic fistula, reoperation, tumor size, blood loss, operation time, and hospital stay, to compare these two surgical approaches. Subgroup analyses were further performed based on high-quality studies using a Newcastle–Ottawa score ≥7 and > 50 cases in laparoscopic and minimally invasive approaches to reduce to some extent the heterogeneity of results. Despite the above, the study has several issues that should be considered. First, the inclusion criteria mentioned in this article were “patients with benign or low-grade malignant tumors in the distal pancreas”; however, several of the analyzed studies included patients with histopathological diagnosis of pancreatic ductal adenocarcinoma, mucinous cystadenocarcinoma, and cancer metastasis, all of which are highly aggressive malignancies that do not meet the inclusion criteria. Second, all the included articles were retrospective studies which can frequently be confounded by unrecognizable biases. It has been reported that WT was quicker and easier than SVP-DP, resulting in a shorter operative time and lower blood loss [8]. However, this meta-analysis revealed no significant differences in operative time and blood loss between the two surgical approaches, which Hang et al. attributed to improvements in technology and surgeons' proficiency, more advanced instruments, and larger sample sizes. Although SVP is the preferred procedure for surgeons in most cases, it is sometimes difficult to preserve splenic vessels in patients with abnormally large tumors or tumors attached to splenic vessels, necessitating intraoperative conversion to WT. This passive conversion can lead to significantly increased operative time and blood loss in WT, which may have affected the results of the meta-analysis. Finally, with such significant heterogeneity detected in some of the outcomes, sensitivity analyses should have been conducted to assess the reliability of the results and to identify the sources of heterogeneity. In conclusion, we highly appreciate the authors' efforts in reviewing the efficacy of SVP versus WT in spleen-preserving DP to provide an improved evidence-based foundation for clinical decision-making. In the future, additional well-designed and multicenter randomized controlled trials are required to further confirm the efficacy of WT and SVP for benign or low-grade malignant pancreatic tumors. In addition, we believe that efforts should be made to improve the original surgical approaches to obtain better clinical results. Ethical approval Not applicable for this study. Sources of funding This work was supported by Key Research and Development Project of the Science & Technology Department of Sichuan Province (Nos.22ZDYF1898 and Nos.2021YFS0231). Author contribution Benjian Gao: study design and writing. Song Su: editing. Xiaoli Yang and Bo Li: critical review and supervision. Research registration unique identifying number (UIN) Name of the registry: Not applicable. Unique Identifying number or registration ID: Not applicable. Hyperlink to your specific registration (must be publicly accessible and will be checked): Not applicable. Guarantor Benjian Gao and Bo Li. Provenance and peer review Commentary, internally reviewed. Declaration of competing interest None. Benjian Gao Song Su Xiaoli Yang Bo Li aDepartment of General Surgery (Hepatobiliary Surgery), The Affiliated Hospital of Southwest Medical University, Luzhou, 646000, Sichuan Province, China bAcademician (Expert) Workstation of Sichuan Province, Luzhou, 646000, Sichuan Province, China cNuclear Medicine and Molecular Imaging Key Laboratory of Sichuan Province, Luzhou, 646000, Sichuan Province, China E-mail addresses:[email protected]; [email protected]