PS02.002: EN-BLOC MEDIASTINAL LYMPH NODE DISSECTION USING A LAPAROSCOPIC TRANSHIATAL APPROACH FOR ESOPHAGEAL AND ESOPHAGOGASTRIC JUNCTION CANCERS

Background The procedure for mediastinal lymph node dissection using a laparoscopic transhiatal approach (LTHA) had not been established for esophageal and esophagogastric junction (EGJ) cancers because of the difficulties associated with surgery. We developed a novel and simple technique for their en-bloc dissection using LTHA. To date, 296 patients had undergone our method during various esophageal surgical procedures, including 39 cases with EGJ cancer. We describe our technique and evaluate the optimal range of mediastinal lymph node dissection for EGJ cancer. Methods The esophageal hiatus was opened and CO2 was introduced into the mediastinum. The posterior plane of the pericardium was extended, and the anterior side of the subcarinal, main bronchial, thoracic paraaortic and pulmonary ligament lymph nodes were separated. The posterior side of these lymph nodes was then separated. Finally, while lifting lymph nodes like a membrane, they were resected from bilateral mediastinal pleura, main bronchi and tracheal bifurcation. Results 1) Patients with EGJ cancers performed middle and lower mediastinal lymph node dissection by LTHA (n = 39) were compared with those performed by the right thoracotomy (n = 41). The total operative time and bleeding were significantly decreased by LTHA. The number of resected middle and lower mediastinal lymph nodes, pR0 rate, and mediastinal recurrence in the two groups were not different. In 87.2% of patients treated by LTHA, extubation was performed at 0 POD. Postoperative respiratory complications was decreased by LTHA (LTHA: 7.7%, thoracotomy: 17.0%). 2) Patients with EGJ cancers performed total mediastinal lymph node dissection by thoracotomy for the time before introducing LTHA were analyzed (n = 37). Upper and/or middle mediastinal lymph nodes metastasis was observed in 10 cases, and all of them had advanced tumors. All of 6 cases with upper mediastinal lymph nodes metastasis were squamous cell carcinoma. Even in adenocarcinoma, middle mediastinal lymph node metastasis was observed in 2 cases, suggesting the importance of mediastinal lymph node dissection for advanced EGJ cancers. Conclusion Our surgical procedure resulted in a good surgical view, safe en-bloc mediastinal lymph node dissection, and the decrease of postoperative respiratory complications. Disclosure All authors have declared no conflicts of interest.