Prognostic significance of number of lymph node metastasis on survival in patients with pathological T3 esophageal carcinoma

The aim of this study was to evaluate the impact of the number of metastatic lymph nodes (MLN) and other risk factors on survival in patients with pathological T3 (pT3) esophageal carcinoma who were treated by esophagectomy. We analyzed 70 patients who received primary curative resection for pT3 esophageal cancer from 1997 to 2011. The prognostic role of age, gender, tumor location, cell type, pathological lymph node status (pN), number of MLNs (<3 vs >=.3), metastatic lymph node ratio (MLR), type of resection, local recurrence, and distant metastasis on overall survival (OS) were examined by univariate and multivariate analyses. Survival curves were calculated using Kaplan-Meier method and survival differences were assessed by log-rank test. A receiver operating characteristic analysis was used to determine the optimum cut-off point for the MLR. The median follow-up time was 42 (range, 8-128) months, and the 1-, 3- and 5-year OS rates were 78.6%, 38.1%, and 22.5%, respectively. Tumor location, pN, the number of MLNs, local recurrence, and distant metastasis had a significant effect on OS in the univariate analysis. In the multivariate model, the number of MLNs (p=0.02; hazard ratio (HR), 2.1; 95% confidence interval (CI), 1.1-4.1) and distant metastasis (p=0.007; HR, 5.1; 95% CI, 1.5-16.8) were independent risk factors for OS. Patients with pT3 esophageal cancer who have 3 or more MLNs and distant metastasis have a poor OS, and this result can be used as a factor for better estimation of prognosis.