title: Can the new American Joint Committee on Cancer staging system predict survival in rectal cancer patients treated with curative surgery following preoperative chemoradiotherapy?
abstract: BACKGROUND
  Although ypStage has been known as a strong prognosticator of recurrence and survival, the detailed interaction of ypT and ypN classification on a survival rate has never been evaluated.
  
  
  METHODS
  Between October 2001 and December 2007, in total, 960 patients with locally advanced rectal cancer were enrolled retrospectively at 3 centers. Five-year overall survival (OS) and disease-free survival (DFS) rate were calculated for each ypTN classification.
  
  
  RESULTS
  The ypT classification interacted with ypN classification to affect survival in most categories. Patients with ypStage 0 and I cancers showed a >90% 5-year OS (ypStage 0, 96.5%; ypStage I, 92.9%; P = .346) and 5-year DFS (ypStage 0, 90.2%; ypStage I, 90.7%; P = .879). Among ypStage III subgroups, large differences in 5-year OS (ypStage IIIA, 90.1%; ypStage IIIB, 68.3%; ypStage IIIC, 40.5%; P < .001) and 5-year DFS (ypStage IIIA, 74.8%; ypStage IIIB, 55.1%; ypStage IIIC, 12.3%; P < .001) were observed. OS and DFS in patients with ypStage IIIA disease were similar to or greater than those in patients with ypStage IIA or IIB/IIC disease. Four patient risk groups were defined: 1) low (ypT0-isN0, ypT1N0, ypT2N0), 2) intermediate (ypT0-2N1, ypT3N0), 3) moderately high (ypT0-2N2, ypT3N1, ypT4N0), and 4) high risk (ypT3N2, ypT4N1-2). Risk grouping showed a narrower range of survival rate compared with ypStage grouping.
  
  
  CONCLUSIONS
  ypStage in rectal cancer, defined according to the 7th edition of the American Joint Committee on Cancer staging system, predicts survival for most ypNT classifications. However, patients with ypStage I rectal cancer have a similar prognosis to those with ypStage 0 cancer, and risk grouping reflects more precise survival outcomes than ypStage.
authors.affiliation: Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Korea.
authors.forename: Sang Hui
authors.initials: SH
authors.lastname: Moon
authors.forename: Dae Yong
authors.initials: DY
authors.lastname: Kim
authors.forename: Ji Won
authors.initials: JW
authors.lastname: Park
authors.forename: Jae Hwan
authors.initials: JH
authors.lastname: Oh
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Chang
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Kim
authors.forename: Tae Hyun
authors.initials: TH
authors.lastname: Kim
authors.forename: Hee Chul
authors.initials: HC
authors.lastname: Park
authors.forename: Doo Ho
authors.initials: DH
authors.lastname: Choi
authors.forename: Ho-Kyung
authors.initials: HK
authors.lastname: Chun
authors.forename: Jong Hoon
authors.initials: JH
authors.lastname: Kim
authors.forename: Jin-Hong
authors.initials: JH
authors.lastname: Park
authors.forename: Chang Sik
authors.initials: CS
authors.lastname: Yu
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D059248:Chemoradiotherapy; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging / Q000379:methods*; D011379:Prognosis; D012004:Rectal Neoplasms / Q000401:mortality* / Q000473:pathology* / Q000628:therapy; D012189:Retrospective Studies; D015996:Survival Rate; D055815:Young Adult