Prognostic significance of lymph node ratio in esophageal cancer.

N staging predicting esophageal cancer patient prognosis has been studied. Lymph node ratio, which is considered to show metastatic lymph node status more accurately, is found to have prognostic significance in several tumors. We investigated whether lymph node ratio (LNR) was associated with the prognosis of esophageal cancer in this study. Esophageal cancer patients who underwent esophagectomy at Qilu Hospital of Shandong University from January 2007 to December 2008 were studied. A total of 209 cases were evaluated in this study. The median disease-free survival (DFS) of this cohort was 35.2 months, and 5-year DFS rate was 32.1%. The median overall survival (OS) was 46.4 months, and 5-year OS rate was 40.0%. Kaplan-Meier survival analysis revealed that patients with LNR higher than 0.2 had significantly poorer DFS (p < 0.001) and OS (p < 0.001) than those with LNR less than 0.2. In a multivariate analysis, LNR was found to be an independent prognostic factor for DFS (p = 0.008, HR 1.863, 95% CI 1.180-2.942) and OS (p = 0.025, HR 1.708, 95% CI 1.068-2.731). N stage (p = 0.028, HR 1.626, 95% CI 1.055-2.506) was also found to be an independent prognostic factors for OS. Subgroups analysis revealed significant difference in OS and DFS rates between different LNR categories within the same N stages (p < 0.05) but not between different N stages within the same LNR category (p > 0.05). LNR was recognized as an independent factor in both OS and DFS in esophageal cancer. Besides, LNR showed a better prognostic value than N stage for esophageal cancer.