title: Is the prediction of prognosis not improved by the seventh edition of the TNM classification for colorectal cancer? Analysis of the surveillance, epidemiology, and end results (SEER) database.
abstract: BACKGROUND
  Whether the 7th edition of American Joint Committee on Cancer (AJCC) TNM staging system (AJCC-7) is a successful revision remains debatable. We aimed to compare the predictive capacity of the AJCC-7 for colorectal cancer with the 6th edition of the AJCC TNM staging system (AJCC-6).
  
  
  METHODS
  The National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) dataset consisting of 158,483 records was used in this study. We evaluated the predictive capacity of the two editions of the staging system using Harrell's C index and Bayesian Information Criterion (BIC).
  
  
  RESULTS
  There was a significant prognostic difference between patients at stage IIB and IIC (P < 0.001). Stage III patients with similar prognoses were adequately sub-grouped in the same stage according to AJCC-7. The Harrell's C index revealed a value of 0.7692 for AJCC-7, which was significantly better than 0.7663 for AJCC-6 (P < 0.001). BIC analysis provided consistent results (P < 0.001).
  
  
  CONCLUSIONS
  This study demonstrates that AJCC-7 is superior to the AJCC-6 staging system in predictive capacity.
authors.affiliation: Department of Surgical Oncology and General Surgery, the First Hospital of China Medical University, Shenyang City, PR China.
authors.forename: Peng
authors.initials: P
authors.lastname: Gao
authors.forename: Yong-xi
authors.initials: YX
authors.lastname: Song
authors.forename: Zhen-ning
authors.initials: ZN
authors.lastname: Wang
authors.forename: Ying-ying
authors.initials: YY
authors.lastname: Xu
authors.forename: Lin-lin
authors.initials: LL
authors.lastname: Tong
authors.forename: Jing-xu
authors.initials: JX
authors.lastname: Sun
authors.forename: Miao
authors.initials: M
authors.lastname: Yu
authors.forename: Hui-mian
authors.initials: HM
authors.lastname: Xu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D011237:Predictive Value of Tests; D011379:Prognosis; D018426:SEER Program