Background: The prognostic value of metastatic lymph node ratio (LNR) is still controversial in esophageal cancer.
Aim: This study aimed to compare the impact of AJCC N staging system (pN) and LNR on the prediction of long-term survival of patients with esophageal carcinoma.
Methods: A total of 496 patients were retrospectively analyzed who underwent esophageal resection at Henan Tumor Hospital from January 2006 to December 2010. The Kaplan-Meier method and log-rank test were used to estimate survival curves. Univariate and multivariate analyses were performed to compare prognostic factors for long-term survival. The difference between pN and LNR with overall survival (OS) was compared by receiver operating characteristic (ROC) curve and area under the curve (AUC).
Results: The 1-, 3-, 5-year overall survival rates of 496 patients were 73.6, 47.1 and 34.2 %, respectively. Univariate analyses showed that diseased region, tumor length, depth of tumor invasion, pN and LNR affected the prognosis, and multivariate analyses demonstrated that depth of tumor invasion, pN and LNR were independent risk factors. Among the three significant variables verified by multivariate analyses, LNR was the best for inadequately staged patients (<12 examined LNs). ROC analyses showed that compared with pN (AUC = 0.579, p = 0.037), LNR (AUC = 0.680, p = 0.002) had better predictive value (z = 2.275, p = 0.029).
Conclusions: LNR has greater prognostic value than pN for esophageal squamous cell carcinoma, especially for patients with <12 LNs removed.