[The application of the en bloc resection for robot-assisted esophageal suspension-traction combined with the "four-edge" dissociation in the lymph node dissection of left recurrent laryngeal nerve of esophageal squamous cell carcinoma].

Objective: To examine the clinical application value of robot-assisted esophageal suspension-traction combined with the "four-edge" dissociation in the lymph node dissection of left recurrent laryngeal nerve of esophageal squamous cell carcinoma. Methods: This is a retrospective case series study. A retrospective analysis was conducted on 127 cases of robot-assisted McKeown minimally invasive esophagectomy (MIE) with complete medical records and follow-up data, and without neoadjuvant therapy, performed at the Department of Minimally Invasive Esophagus Surgery, Tianjin Medical University Cancer Institute and Hospital from January 2022 to December 2024. Among them, there were 116 males and 11 females, aged (63.0±6.0) years (range: 44 to 79 years). There were 13 cases of upper thoracic esophageal cancer, 69 cases of middle thoracic esophageal cancer, and 45 cases of lower thoracic esophageal cancer. The lymph node dissection method in the 106recL station was the en bloc resection for robot-assisted esophageal suspension-traction combined with the "four-edge" dissociation. Under the assistance of the robot, the operating space in the left recurrent laryngeal nerve area was increased and exposed by suspending and pulling the esophagus; through dissociating the outer edges of the trachea, esophagus, blood vessels and nerves, the operating space was further released and bloodless was performed, thereby achieving en bloc resection of the soft tissue and lymph nodes in the left recurrent laryngeal nerve area. Statistical methods such as χ2 test and univariate and multivariate Logistic regression were employed to analyze the relationship between lymph node metastasis in the 106recL station and clinical pathological characteristics. Results: Among the 127 cases of robot-assisted McKeown MIE, a total of 508 lymph nodes were dissected in the 106recL station. There were 21 cases of lymph node metastasis in the 106recL station, with a metastasis rate of 16.54% (21/127), and the metastasis was closely related to the location of the tumor and T stage (both P<0.05). Univariate and multivariate Logistic regression analysis showed that upper thoracic tumor (OR=3.353, 95%CI: 2.684 to 189.852, P=0.005), middle thoracic tumor (OR=2.597, 95%CI: 1.886 to 75.735, P=0.013), T4a stage (OR=1.928, 95%CI: 1.250 to 31.887, P=0.039) were independent risk factors for lymph node metastasis in the 106recL station of esophageal cancer. Among the 127 postoperative patients, 7 cases (5.5%) had hoarseness, 9 cases (7.1%) had pulmonary infection, 2 cases (1.6%) had anastomotic fistula, and 3 cases (2.4%) had recurrence of upper mediastinal lymph nodes. Conclusions: In McKeown MIE, the use of the en bloc resection for robot-assisted esophageal suspension-traction combined with the "four-edge" dissociation for lymph node dissection in the 106recL station is safe and effective, and the dissection of lymph nodes in the 106recL station is more clinically valuable in upper thoracic, middle thoracic esophageal cancer and those with a later T stage.