title: Proposed Modification of Nodal Staging as an Alternative to the Seventh Edition of the American Joint Committee on Cancer Tumor-Node-Metastasis Staging System Improves the Prognostic Prediction in the Resected Esophageal Squamous-Cell Carcinoma.
abstract: BACKGROUND
  The 7th American Joint Committee on Cancer (AJCC) tumor-node-metastasis staging system for esophageal cancer defined N classification based on the number of metastatic lymph nodes (LNs). However, this classification might neglect the extent of LNs metastasis. This study aimed to revise N classification based on the extent of LNs metastasis and propose a modification to the current AJCC staging system for better representing the prognostic characteristics of Chinese esophageal squamous-cell carcinoma (ESCC).
  
  
  METHODS
  We retrospectively reviewed 1993 ESCC patients who underwent curative resection. The proposed N categories based on the number of LNs metastasis stations were compared with the current staging system by univariate and multivariate Cox regression analyses. Homogeneity, discriminatory ability, and monotonicity of gradients of two staging systems were compared using likelihood ratio χ statistics and Akaike information criterion calculations.
  
  
  RESULTS
  The survival differences were not significant for N2 versus N3 category (p = 0.231) and stages IIIB versus IIIC (p = 0.713) based on the 7th AJCC staging system. When the modified staging system was adopted, the survival difference for N2 versus N3 and IIIB versus IIIC could be well discriminated. Statistical analysis showed that the modified staging system had higher likelihood ratio χ scores and smaller Akaike information criterion values than the 7th AJCC staging system, which represented the optimum prognostic stratification.
  
  
  CONCLUSIONS
  The modified staging system with the revised N categories based on the number of LNs metastasis stations better predicts the survival of Chinese ESCC population than the 7th AJCC staging system. Further studies are required to confirm this result.
authors.affiliation: *Department of Tumor Biological Treatment, The Third Affiliated Hospital, Soochow University, Changzhou, China; †Department of Radiation Oncology, the Third Affiliated Hospital, Soochow University, Changzhou, China; and ‡Department of Thoracic Surgery, The Third Affiliated Hospital, Soochow University, Changzhou, China.
authors.forename: Zhong-hua
authors.initials: ZH
authors.lastname: Ning
authors.forename: Zhi-gang
authors.initials: ZG
authors.lastname: Wang
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Xiao-dong
authors.initials: XD
authors.lastname: Li
authors.forename: Lu-jun
authors.initials: LJ
authors.lastname: Chen
authors.forename: Bin
authors.initials: B
authors.lastname: Xu
authors.forename: Wen-dong
authors.initials: WD
authors.lastname: Gu
authors.forename: Ying-jie
authors.initials: YJ
authors.lastname: Shao
authors.forename: Yun
authors.initials: Y
authors.lastname: Xu
authors.forename: Jin
authors.initials: J
authors.lastname: Huang
authors.forename: Hong-lei
authors.initials: HL
authors.lastname: Pei
authors.forename: Jing-ting
authors.initials: JT
authors.lastname: Jiang
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000145:classification* / Q000473:pathology*; D004938:Esophageal Neoplasms / Q000145:classification* / Q000473:pathology*; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging / Q000379:methods / Q000592:standards; D011379:Prognosis; D014481:United States