title: Maximum Ki-67 staining in prostate cancer provides independent prognostic information after radical prostatectomy.
abstract: BACKGROUND
  We have evaluated the prognostic value of Ki-67 growth fraction after radical prostatectomy, especially focusing on intermediate grade carcinomas.
  
  
  METHODS
  104 patients treated by radical prostatectomy for clinically localized prostate cancer were studied. The area of highest tumour grade was selected from the prostatectomy specimens and used for Ki-67 immunostaining The fraction of Ki-67 positive tumour nuclei in the area of most intense proliferation ("hot spot") was estimated, and related to biochemical failure.
  
  
  RESULTS
  Ki-67 expression (median 6.7%, range 1.2-42.6%) was significantly associated with WHO histological grade. In univariate analysis of all 104 carcinomas, Ki-67 expression was associated with time to biochemical failure as were age, tumour dimension, WHO histological grade, pathological stage, positive surgical margins and pre-operative s-PSA. In multivariate Cox' analysis, Ki-67 expression, pathological stage and pre-operative s-PSA remained as independent predictors of time to biochemical failure. Ki-67 expression (HR 4.8, p < 0.001) was also found to be an independent predictor among moderately-differentiated carcinomas.
  
  
  CONCLUSIONS
  Estimates of Ki-67 growth fraction in areas of highest tumour grade may prove to be a useful prognostic biomarker after radical prostatectomy.
authors.affiliation: Department of Pathology, The Gade Institute, Bergen, Norway. ole.halvorsen@gades.uib.no
authors.forename: O J
authors.initials: OJ
authors.lastname: Halvorsen
authors.forename: S
authors.initials: S
authors.lastname: Haukaas
authors.forename: P A
authors.initials: PA
authors.lastname: Høisaeter
authors.forename: L A
authors.initials: LA
authors.lastname: Akslen
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D018572:Disease-Free Survival; D006801:Humans; D019394:Ki-67 Antigen / Q000096:biosynthesis*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D013194:Staining and Labeling / Q000379:methods
chemical_list: D019394:Ki-67 Antigen