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, the authors aimed to investigate how the number of dissected lymph nodes (LNs) during esophagectomy for esophageal squamous cell carcinoma impacts overall survival (OS), particularly that of patients with positive LNs.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 LNs during surgery was 24; therefore, patients with 15-23 and those with 24 or more resected LNs were assigned to subgroups A and B, respectively.Results: After a median follow-up of 60.33 months, 1624 patients who underwent esophagectomy were evaluated; 60.53 and 39.47% had a pathological diagnosis of N + or N0, respectively. The median OS was 33.9 months for the N + group; however, the N0 group did not achieve the median OS. The mean OS was 84.9 months. In the N + group, the median OS times of subgroups A and B were 31.2 and 37.1 months, respectively. The OS 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 LNs harvested during surgery to 24 or more could improve the OS of patients with positive LNs but not that of patients with negative LNs.