Basic Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Surg. May 27, 2023; 15(5): 812-824
Published online May 27, 2023. doi: 10.4240/wjgs.v15.i5.812
Distribution of splenic artery lymph nodes and splenic hilar lymph nodes
Yuya Umebayashi, Satoru Muro, Masanori Tokunaga, Toshifumi Saito, Yuya Sato, Toshiro Tanioka, Yusuke Kinugasa, Keiichi Akita
Yuya Umebayashi, Masanori Tokunaga, Toshifumi Saito, Yuya Sato, Toshiro Tanioka, Yusuke Kinugasa, Department of Gastrointestinal Surgery, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
Satoru Muro, Keiichi Akita, Department of Clinical Anatomy, Tokyo Medical and Dental University, Tokyo 113-8519, Japan
Author contributions: Umebayashi Y, Muro S, Tokunaga M, Saito T, Sato Y, Tanioka T, Kinugasa Y and Akita K designed and coordinated the study; Umebayashi Y, Muro S and Saito T acquired data; Umebayashi Y and Muro S analyzed data; Umebayashi Y, Muro S, Sato Y, Tokunaga M and Akita K interpreted the data; Umebayashi Y, Muro S, Tokunaga M and Akita K drafted the manuscript; all authors approved the final version of the article.
Institutional review board statement: The study was reviewed and approved by the Institutional Review Board at Tokyo Medical and Dental University.
Informed consent statement: All study participants, or their legal guardian, provided informed written consent prior to study enrollment.
Conflict-of-interest statement: All authors have nothing to disclose.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Masanori Tokunaga, MD, PhD, Associate Professor, Department of Gastrointestinal Surgery, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
Received: December 28, 2022
Peer-review started: December 28, 2022
First decision: February 4, 2023
Revised: February 18, 2023
Accepted: April 7, 2023
Article in press: April 7, 2023
Published online: May 27, 2023
Research background

In East Asian countries, the standard treatment for locally advanced proximal gastric cancer with invasion of the greater-curvature is total gastrectomy with splenectomy. The splenic hilar and splenic artery lymph nodes (LNs) are usually dissected in this procedure. However, this procedure increases the risk of postoperative pancreatic complications. To avoid these complications, laparoscopic spleen-preserving splenic hilar LN dissection (SPSHLD) has been developed and is widely used in some countries.

Research motivation

Performing laparoscopic SPSHLD without spleen mobilization makes it challenging to dissect posterior splenic hilar LNs and LNs along the splenic artery. While previous studies have demonstrated the clinical feasibility of laparoscopic SPSHLD, anatomical studies have not been performed. Therefore, we sought to justify the omission of the posterior splenic portal LN from an anatomical perspective.

Research objectives

To evaluate the feasibility of laparoscopic SPSHLD from an anatomical standpoint, this study aimed to demonstrate the detailed distribution pattern of the anterior and posterior LNs, clarify the anatomical distribution of the splenic hilar (No. 10) and splenic artery (No. 11p and 11d) LNs, and count the number of anterior and posterior LNs.

Research methods

This study examined six Japanese cadavers fixed by arterial perfusion with 8% formalin and preserved in 30% alcohol. The distribution of the splenic hilar LNs and splenic artery LNs was evaluated by creating histological sections, followed by hematoxylin & eosin staining to assess the structure of the organs and vasculature. In addition, the number of anterior and posterior LNs was counted, and three-dimensional reconstructions of their distributions were created.

Research results

This research uncovered a pattern where No. 11 LNs exhibited a greater frequency on the anterior side than on the posterior side, whereas No. 10 LNs showed minimal variability in number. The mean LN count was observed to be higher on the anterior side for No. 11p, No. 11d, and No. 10 LNs. Additionally, the number of LNs on the posterior side tended to increase toward the splenic hilum. Heat maps and three-dimensional images were generated to illustrate the spatial distribution and location of the LNs, showing that some LNs were intravascular or surrounded by the hilar vessels.

Research conclusions

The ratio of anterior to posterior splenic hilar and splenic artery LNs may be lower than expected, and the number of posterior LNs increased toward the hilum. Our study suggests that surgeons should be aware that some posterior No. 10 and 11d LNs may be left behind after SPSHLD when using this procedure in clinical practice.

Research perspectives

In laparoscopic SPSHLD, some LNs may not be retrieved, which should be considered by surgeons.