Comparison of the 7th and proposed 8th editions of the AJCC/UICC TNM staging system for esophageal squamous cell carcinoma underwent radical surgery

Abstract

BackgroundRecently, the 8th edition of the TNM classification of esophageal cancer has come up. The present study aims to compare the 7th and the proposed 8th edition of the AJCC/UICC TNM staging system for esophageal squamous cell carcinoma (ESCC). MethodsA total of 1872 ESCC patients who underwent radical surgery with curative intent were analyzed retrospectively. Survival was analyzed using the Kaplan–Meier method, and values were compared using the log-rank test. Multivariate analysis was performed using the Cox proportional hazard model. The Akaike information criterion (AIC) and the concordance index (c-index) were applied to compare the two prognostic systems. ResultsOn univariate analysis, the 7th staging system, the proposed 8th staging system, gender, age as well as adjuvant treatment were found to have significant association with overall survival (OS). In both the current staging system and the modified version, age and gender were independent prognostic factors in a multivariate analysis. The AIC value for the proposed 8th version was smaller than that for the 7th staging system; the c-index value for the proposed 8th version was larger than that for the 7th staging system. Subgroup analysis in patients with/without nodal metastasis obtained consistent results. ConclusionBased on the data from our single center, the proposed 8th AJCC staging system seems to be superior to the 7th AJCC staging system in terms of OS for patients with thoracic ESCC who underwent radical surgery.