title: Recommendations for Updating T and N Staging Systems for Nasopharyngeal Carcinoma in the Era of Intensity-Modulated Radiotherapy.
abstract: OBJECTIVE
  The aim of this study was to compare the 2008 Chinese and the 7th edition of the American Joint Committee on Cancer (AJCC) staging systems for nasopharyngeal carcinoma and to provide proposals for updating T and N staging systems of the present staging system.
  
  
  METHODS
  Between January 2007 and December 2012, a cohort of 752 patients with biopsy-proven, newly diagnosed, non-metastatic nasopharyngeal carcinoma who were treated with intensity-modulated radiotherapy were retrospectively analysed. Prognoses were compared by T stage, N stage, and clinical stage according to the two staging systems for overall survival (OS), local relapse-free survival (LRFS), and distant metastasis-free survival (DMFS).
  
  
  RESULTS
  In terms of both the T and N staging systems, the two current staging systems were comparable in predicting OS. The T classification of the 2008 Chinese staging system was better in predicting LRFS, while the N classification of the 7th edition AJCC staging system was superior in predicting DMFS. In the modern era of intensity-modulated radiotherapy, the staging system should be updated by down-staging the current stage T2 to T1, and it might be rational to merge subcategories N1 and N2.
  
  
  CONCLUSIONS
  The two current staging systems each had advantages in predicting prognosis. It seems reasonable to downstage T2 to T1 and to merge N1 and N2.
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Zhong-Guo
authors.initials: ZG
authors.lastname: Liang
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Xiao-Qian
authors.initials: XQ
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Zhi-Jie
authors.initials: ZJ
authors.lastname: Niu
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Kai-Hua
authors.initials: KH
authors.lastname: Chen
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Ling
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Song
authors.initials: S
authors.lastname: Qu
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Fang
authors.initials: F
authors.lastname: Su
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhao
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Ye
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Xin-Bin
authors.initials: XB
authors.lastname: Pan
authors.affiliation: Department of Radiation Oncology, The Affiliated Tumor Hospital of Guangxi Medical University, Cancer Institute of Guangxi Zhuang Autonomous Region, Nanning, P.R. China.
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Zhu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002277:Carcinoma / Q000175:diagnosis* / Q000532:radiotherapy*; D002681:China; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis* / Q000532:radiotherapy*; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local; D009367:Neoplasm Staging / Q000379:methods*; D011379:Prognosis; D050397:Radiotherapy, Intensity-Modulated; D012189:Retrospective Studies; D012955:Societies, Medical; D014481:United States; D055815:Young Adult