title: Evaluation of UICC-TNM and JSBS staging systems for surgical patients with extrahepatic cholangiocarcinoma.
abstract: OBJECTIVE
  Two staging systems exist to classify extrahepatic cholangiocarcinoma (EHC), the TNM staging of the International Union Against Cancer (UICC) and the classification system of the Japanese Society of Biliary Surgery (JSBS). This study sought to evaluate the utility of these two staging systems.
  
  
  METHODS
  One hundred and twenty eight consecutive patients who underwent surgical resection were retrospectively classified into the appropriate stages using the UICC-TNM and JSBS systems. We also compared the distribution and survival curves of respective stages.
  
  
  RESULTS
  Although the UICC-TNM staging system divided patients into seven categories, 106 of 128 patients (82.8%) fell into three stages (stages IA, IIA, or IIB). In contrast, patients were relatively evenly divided across the five categories in JSBS staging. The survival curve of UICC-TNM stage IIB was more similar to stage IV than stages IIA or III; survival rates for stages IIB and IV were significantly lower than the other stages. According to the JSBS staging system, there were significant differences between stages I and III, IVA and IVB, and II and IVA/IVB, and III and IVA/IVB.
  
  
  CONCLUSIONS
  Patients who underwent surgical resection were not evenly divided across UICC-TNM staging categories in comparison to JSBS staging. Stratification of survival ability was better when using the JSBS staging in comparison to the UICC-TNM system. The better understanding about distribution of patient classified by stage and stratification ability of survival of these two staging system may help surgeons assess the patients with EHC.
authors.affiliation: Department of Surgery, University of Tsukuba, Graduate School of Comprehensive Human Sciences, 1-1-1, Tennodai, Tsukuba, 305-8575, Japan. rsasaki@md.tsukuba.ac.jp
authors.forename: Ryoko
authors.initials: R
authors.lastname: Sasaki
authors.forename: Soichiro
authors.initials: S
authors.lastname: Murata
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Oda
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Ohkohchi
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Takeda
authors.forename: Go
authors.initials: G
authors.lastname: Wakabayashi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018281:Cholangiocarcinoma / Q000473:pathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis