Resected lymph nodes and survival of patients with esophageal squamous cell carcinoma: an observational study

Background: The incidence and mortality of esophageal cancer are high. Therefore, we aimed to investigate how the number of dissected lymph nodes during esophagectomy for esophageal squamous cell carcinoma impacts overall survival, particularly that of patients with positive lymph nodes. Materials and methods: Data from 2010 to 2017 were obtained from the Sichuan Cancer Hospital and Institute Esophageal Cancer Case Management Database. Participants were divided into two groups: patients with negative lymph nodes (N0) and patients with positive lymph nodes (N+). The median number of resected lymph nodes during surgery was 24; therefore, patients with 15 to 23 and those with 24 or more resected lymph nodes were assigned to subgroups A and B, respectively. Results: After a median follow-up of 60.33 months, 1,624 patients who underwent esophagectomy were evaluated; 60.53% and 39.47% had a pathological diagnosis of N+ or N0, respectively. The median overall survival was 33.9 months for the N+ group; however, the N0 group did not achieve the median overall survival. The mean overall survival was 84.9 months. In the N+ group, the median overall survival times of subgroups A and B were 31.2 and 37.1 months, respectively. The overall survival rates at 1, 3, and 5 years were 82%, 43%, and 34%, respectively, for subgroup A of the N+ group; they were 86%, 51%, and 38%, respectively, for subgroup B of the N+ group. Subgroups A and B of the N0 group exhibited no statistically significant differences. Conclusion: Increasing the number of lymph nodes harvested during surgery to 24 or more could improve the overall survival of patients with positive lymph nodes but not that of patients with negative lymph nodes. Export