A comparative study of the short-term efficacy and long-term efficacy of systematic lymph node dissection and elective lymph node dissection in patients with early esophageal cancer

Abstract

Objective: To investigate the feasibility, safety, short-term efficacy and long-term efficacy of elective lymph node dissection in patients with early esophageal cancer. Methods: The study retrospectively evaluated 405 patients with cT1N0M0 esophageal carcinoma who received minimally invasive esophagectomy in the First Affiliated Hospital of University of Science and Technology of China between March 2007 and March 2013. Of those patients, 208 patients underwent systematic lymph node dissection (SLND) and 197 patients underwent elective lymph node dissection (ELND). The clinicopathologic factors, operational factors, postoperative complications, lymph node dissection and prognosis of patients were compared by independent sample t test, χ(2) test, or Mann-Whitney rank test. The 5-year overall survival was calculated by the Kaplan-Meier estimation method using the Log-rank test. Results: There was no significant difference in clinicopathological data between the SLND group and the ELND group. The incidence of pulmonary infection (8.2% vs. 2.9%, P=0.04) and arrhythmia (6.2% vs. 2.0%, P=0.03) of the minor postoperative complications in the SLND group were higher than the ELND group. The incidence of pulmonary infection (6.2% vs. 2.0%, P=0.03), Chylothorax (5.8% vs.1.5%, P=0.02), anastomotic or pleural hemorrhage requiring reoperation (2.9% vs.0.5%, P=0.04) of major postoperative complications in the SLND group were higher than the ELND group, the difference was statistically significant. In the perioperative data of two groups, the incidence of total postoperative complications, total pulmonary complications, operation time, intraoperative blood loss, postoperative hospitalization, postoperative thoracic drainage duration and postoperative thoracic drainage fluid volume of the SLND group were higher than the ELND group, the difference was statistically significant. The mean numbers and stations of dissected lymph node in the SLND were 30.2±4.2 and 12.1±2.7, the mean numbers and stations of dissected lymph node in the ELND were 25.7±3.8 and 8.4±3.6. The survival rates of 1, 3, 5 years of all patients were 100%, 95.9% and 82.5%, respectively. The median survival time was 87.4 months. Further analysis showed that the 1, 3 and 5 years survival rate of patients with stage Ⅰ esophageal cancer was 100%, 97.1% and 88.9%, respectively. The median survival time was 89.3 months. The 1, 3 and 5 years survival rate of patients with stage Ⅱa esophageal cancer was 100%, 93.2% and 76.8%, respectively. The median survival time was 77.2 months. There was no significant difference in survival rate between the SLND group and the ELND group in 1, 3 and 5 years. When taking a further analysis of stage Ⅰ esophageal cancer, the survival rates between 188 patients in the SLND group and 180 patients in the ELND group were no significant difference. When focus on the stage Ⅱa esophageal cancer, the 1, 3 and 5 years survival rate were higher in the SLND group than that in the ELND group (100%, 94.5%, 83.2% vs. 100%, 91.3%, 72.1%, P=0.047), the difference was statistically significant. Conclusion: ELND can be safely and effectively performed for early esophageal cancer with favorable short-term efficacy and long-term efficacy.