Positive lymph node ratio is an important index to predict long-term survival for advanced esophageal squamous carcinoma patients (II∼III) with R0 resection--a SEER-based analysis.

Background: Esophageal squamous carcinoma (ESCC) is one of the most malignant cancers in the world due to nodal metastasis. Therefore, a reasonable nodal staging system is extremely important for further treatment strategies. Recently the positive lymph node ratio (PLNR) is an important prognostic factor in various solid tumors.