Histological study of the structural layers around the esophagus in the lower mediastinum  

作　　者：Toshifumi Saito Satoru Muro Hisashi Fujiwara Yuya Umebayashi Yuya Sato Masanori Tokunaga Keiichi Akita Yusuke Kinugasa 

机构地区：[1]Department of Gastrointestinal Surgery,Tokyo Medical and Dental University,Bunkyo-ku 113-8519,Tokyo,Japan [2]Department of Clinical Anatomy,Tokyo Medical and Dental University,Bunkyo-ku 113-8519,Tokyo,Japan

出　　处：《World Journal of Gastrointestinal Surgery》2023年第7期1331-1339,共9页世界胃肠外科杂志（英文版）（电子版）

摘　　要：BACKGROUND In Japan,the transhiatal approach,including lower mediastinal lymph node dissection,is widely performed for Siewert type II esophagogastric junction adenocarcinoma.This procedure is generally performed in a magnified view using laparoscopy or a robotic system,therefore,the microanatomy of the lower mediastinum is important.However,mediastinal microanatomy is still unclear and classification of lower mediastinal lymph nodes is not currently based on fascia or other microanatomical structures.AIM To clarify the fascia and layer structures of the lower mediastinum and classify the lower mediastinal tissue.METHODS We dissected the esophagus and surrounding organs en-bloc from seven cadavers fixed in 10%formalin.Organs and tissues were then cut at the level of the lower thoracic esophagus,embedded in paraffin,and serially sectioned.Tissue sections were stained with Hematoxylin-Eosin(all cadavers)and immunostained for the lymphatic endothelial marker D2-40(three cadavers).We observed the periesophageal fasciae and layers,and defined lymph node boundaries based on the fasciae.Lymphatic vessels around the esophagus were observed on immunostained tissue sections.RESULTS We identified two fasciae,A and B.We then classified lower mediastinal tissue into three areas,paraesophageal,paraaortic,and intermediate,using these fasciae as boundaries.Lymph nodes were found to be present and were counted in each area.The dorsal part of the intermediate area was thicker on the caudal side than on the cranial side in all cadavers.On the dorsal side,no blood vessels penetrated the fasciae in six of the seven cadavers,whereas the proper esophageal artery penetrated fascia B in one cadaver.D2-40 immunostaining showed lymphatic vessel connections between the paraesophageal and intermediate areas on the lateral and ventral sides of the esophagus,but no lymphatic connection between areas on the dorsal side of the esophagus.CONCLUSION Histological studies identified two fasciae surrounding the esophagus in the lower mediastinum and

关 键 词：Esophagogastric junction HISTOLOGY MEDIASTINUM ADENOCARCINOMA Esophageal cancer Gastric cancer 

分 类 号：R735.1[医药卫生—肿瘤]