title: A comparison between the sixth and seventh editions of the UICC/AJCC staging system for nasopharyngeal carcinoma in a Chinese cohort.
abstract: BACKGROUND
  The International Union Against Cancer/American Joint Committee on Cancer (UICC/AJCC) TNM staging system of nasopharyngeal carcinoma (NPC) is the most important system for survival prediction. The TNM 7th edition UICC/AJCC TNM staging system for NPC was adopted in January 2009, and is now internationally recommended. In comparison with the TNM 6th edition, there were several revisions in the new edition staging system. This study aims to evaluate the prognostic value of the TNM 7th edition for NPC patients in comparison with the TNM 6th edition.
  
  
  METHODS
  Clinical data of 2,629 NPC patients from the Sun Yat-sen University Cancer Center between January 2006 and December 2010 were retrospectively collected and all the patients were restaged according to the criteria of the TNM 6th edition and TNM 7th edition UICC/AJCC staging manual. Univariate and multivariate COX proportional hazards analyses were applied to evaluate the prognostic values between adjacent stage categories of the TNM 6th edition and TNM 7th edition.
  
  
  RESULTS
  In comparison with the TNM 6th edition, a significant alteration of the distribution of N categories was observed when the TNM 7th edition was applied (χ2 = 20.589, P<0.001), with 119 (119/670, 17.8%) patients up-staging from N0 to N1. With regard to T and overall stage, 37 (37/561, 6.6%) patients were down-staged from T2a with the TNM 6th edition to T1 with the TNM 7th edition, and finally two patients were up-staged to overall stage II (2/118, 1.7%). Moreover, the survival curves were significantly segregated (P<0.05) between T1 and T2 as well as N1 and N2 with the TNM 7th edition.
  
  
  CONCLUSIONS
  The TNM 7th edition led to a significant alteration in the distribution of N categories and it is superior to the TNM 6th edition in predicting the frequency of overall survival and distant metastasis-free survival.
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Experimental Research, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China; Department of Oncology, the First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Li
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China.
authors.forename: Xiong
authors.initials: X
authors.lastname: Zou
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Experimental Research, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China.
authors.forename: Yun-Long
authors.initials: YL
authors.lastname: Wu
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Experimental Research, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China.
authors.forename: Jing-Cui
authors.initials: JC
authors.lastname: Guo
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Pathology, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China.
authors.forename: Jing-Ping
authors.initials: JP
authors.lastname: Yun
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Experimental Research, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China.
authors.forename: Miao
authors.initials: M
authors.lastname: Xu
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Experimental Research, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China.
authors.forename: Qi-Sheng
authors.initials: QS
authors.lastname: Feng
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Experimental Research, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China.
authors.forename: Li-Zhen
authors.initials: LZ
authors.lastname: Chen
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Experimental Research, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China.
authors.forename: Jin-Xin
authors.initials: JX
authors.lastname: Bei
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Experimental Research, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China.
authors.forename: Yi-Xin
authors.initials: YX
authors.lastname: Zeng
authors.affiliation: Collaborative Innovation Center for Cancer Medicine, State Key Laboratory of Oncology in South China, Sun Yat-sen University Cancer Center, Guangzhou 510060, P. R. China; Department of Nasopharyngeal Carcinoma, Sun Yat-sen University Cancer Center, No. 651, Dongfeng East Road, Guangzhou 510060, P. R. China.
authors.forename: Ming-Yuan
authors.initials: MY
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma; D002648:Child; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D000077274:Nasopharyngeal Carcinoma; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis / Q000453:epidemiology / Q000473:pathology*; D009305:Nasopharynx / Q000473:pathology*; D009367:Neoplasm Staging / Q000379:methods; D011379:Prognosis; D055815:Young Adult