title: A proposal for reclassification of the Fuhrman grading system in patients with clear cell renal cell carcinoma.
abstract: BACKGROUND
  The conventional Fuhrman grading system, which categorizes renal cell carcinoma (RCC) with grades I, II, III, and IV, is the most widely used predictor assessment of RCC cancer-specific mortality (CSM).
  
  
  OBJECTIVE
  The aim of this study was to test the prognostic ability of simplified Fuhrman grading schemes (FGSs) that rely on two- or three-tiered classifications.
  
  
  METHODS
  The current study addressed a population of 14064 patients with clear cell RCC who were treated with partial or radical nephrectomy between 1988-2004, within nine Surveillance, Epidemiology, and End Results (SEER) cancer registries.
  
  
  METHODS
  Univariable and multivariable analyses as well as prognostic accuracy analyses were performed for various FGSs to test their ability to predict CSM rates. The conventional four-tiered FGS was compared to a modified two-tiered FGS in which grades I and II and grades III and IV were combined. A second simplified three-tiered FGS in which grades I and II were combined but grades III and IV were kept separate was also tested.
  
  
  CONCLUSIONS
  The overall 5-yr CSM-free rate was 81.5%. All three FGSs achieved independent predictor status in multivariable analyses. Prognostic accuracy of multivariable models that relied on various FGSs was 83.6% for the modified two-tiered FGS and 83.8% for both the conventional four-tiered and the modified three-tiered FGS.
  
  
  CONCLUSIONS
  Our findings indicate that the simplified FGSs perform equally as well as the conventional four-tiered FGS. The use of simplified grading schemes may represent an advantage for pathologists as well as for clinicians caring for patients with RCC.
authors: Cancer Prognosis and Health Outcomes Unit, University of Montreal Health Center, Montreal, QC, Canada.
authors: Maxine
authors: M
authors: Sun
authors: Giovanni
authors: G
authors: Lughezzani
authors: Claudio
authors: C
authors: Jeldres
authors: Hendrik
authors: H
authors: Isbarn
authors: Shahrokh F
authors: SF
authors: Shariat
authors: Philippe
authors: P
authors: Arjane
authors: Hugues
authors: H
authors: Widmer
authors: Daniel
authors: D
authors: Pharand
authors: Mathieu
authors: M
authors: Latour
authors: Paul
authors: P
authors: Perrotte
authors: Jean-Jacques
authors: JJ
authors: Patard
authors: Pierre I
authors: PI
authors: Karakiewicz
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000145:classification* / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D003661:Decision Support Techniques; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D007680:Kidney Neoplasms / Q000145:classification* / Q000401:mortality / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000379:methods*; D009392:Nephrectomy; D015588:Observer Variation; D016016:Proportional Hazards Models; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D018426:SEER Program; D009626:Terminology as Topic; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology