The Presence of Metastatic Thoracic Duct Lymph Nodes in Western Esophageal Cancer Patients: A Multinational Observational Study

Background The thoracic lymphadenectomy during an esophagectomy for esophageal cancer includes resection of the thoracic duct (TD) compartment containing the thoracic duct lymph nodes (TDLN). However, the role of TD compartment resection is still a topic of debate since metastatic TDLNs have only been demonstrated in squamous cell carcinomas in Eastern esophageal cancer patients. Therefore, the aim of this study was to assess the presence and metastatic involvement of TDLNs in a Western population, in which adenocarcinoma is the predominant type of esophageal cancer. Methods From July 2017 to May 2020 all consecutive patients undergoing an open or robot-assisted transthoracic esophagectomy with concurrent lymphadenectomy and resection of the TD compartment in the University Medical Center Utrecht, The Netherlands and the Citta della Salute e della Scienza University Hospital in Turin, Italy were included. The TD compartment was resected en bloc and was separated in the operation room by the operating surgeon after which it was macro- and microscopically assessed for (metastatic) TDLNs by the pathologist. Results A total of 117 patients with an adenocarcinoma (73%) or squamous cell carcinoma (27%) of the esophagus were included. In 61 (52%) patients TDLNs were found, containing metastasis in 9 (15%) patients. No major complications related to TD compartment resection were observed. Conclusions This is the first study to demonstrate the presence of metastatic TDLNs in adenocarcinomas of the esophagus. This result provides a valid argument to routinely extend the thoracic lymphadenectomy with resection of the TD compartment during an esophagectomy for esophageal cancer.