title: How far is the preoperative Kattan nomogram applicable for the prediction of recurrence after prostatectomy in patients presenting with PSA levels of more than 20 ng/ml? A validation study.
abstract: OBJECTIVE
  We present an external validation study investigating the applicability of the preoperative Kattan nomogram for predicting recurrence after prostatectomy in a population of patients with serum prostate-specific antigen (PSA) levels exceeding 20 ng/ml.
  
  
  METHODS
  In the evaluation of clinical parameters pooled from a total of 191 patients presenting with PSA levels ranging between 20.1 and 100 ng/ml, the PSA-free survival rate 60 months after surgery was calculated according to Kattan nomograms. Subsequently, the results were statistically compared with the corresponding actual survival rates obtained from Kaplan-Meier analysis. For this purpose, the patients were assigned to one of four different risk groups according to predictions derived from the Kattan nomograms, enabling a direct comparison of expected (as predicted by Kattan nomogram) versus actual survival of each patient investigated in our study.
  
  
  RESULTS
  Predicted PSA-free survival rates were determined to be as follows: 83% (low risk group); 66% (intermediate risk group); 39% (intermediate-high risk group), and 10% (high risk group) in comparison with the actual survival rates determined to be 63, 62, 40 and 21%, respectively. For PSA levels ranging between 20.1 and 30 ng/ml, 30.1 and 50 ng/ml, and 50.1 and 100 ng/dl, PSA-free survival rates were found to be 57, 37, and 27% (p=0.0017), respectively, during a 5-year post-prostatectomy follow-up.
  
  
  CONCLUSIONS
  The Kattan nomogram shows good statistical concordance with actual survival rates in the mean risk quadrants, but considerable differences were demonstrated concerning individuals with either a high or with a low risk of cancer progression.
authors.affiliation: Department of Urology, Carl Thiem Hospital, Cottbus, University Teaching Hospital, Germany. M.May@ctk.de
authors.forename: M
authors.initials: M
authors.lastname: May
authors.forename: S
authors.initials: S
authors.lastname: Gunia
authors.forename: C
authors.initials: C
authors.lastname: Helke
authors.forename: S
authors.initials: S
authors.lastname: Führer
authors.forename: B
authors.initials: B
authors.lastname: Hoschke
authors.forename: D
authors.initials: D
authors.lastname: Fahlenkamp
authors.forename: H
authors.initials: H
authors.lastname: Vogler
authors.forename: M
authors.initials: M
authors.lastname: Siegsmund
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000097:blood*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood* / Q000175:diagnosis; D049451:Nomograms; D011237:Predictive Value of Tests; D011300:Preoperative Care; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood*; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000097:blood / Q000601:surgery*; D012189:Retrospective Studies
chemical_list: D014408:Biomarkers, Tumor; D017430:Prostate-Specific Antigen