title: Development and internal validation of preoperative transition zone prostate cancer nomogram.
abstract: OBJECTIVE
  Up to 20% of men may harbor a transition zone (TZ) prostate cancer (PCa) at radical prostatectomy (RP). TZ PCa may be associated with more favorable RP pathologic findings than peripheral zone (PZ) PCa. To identify these men, we developed a model capable of predicting the probability of TZ PCa at RP.
  
  
  METHODS
  The study cohort consisted of 945 consecutive men treated with RP, with clinical stage, prostate-specific antigen (PSA) level, and detailed biopsy and RP pathology data available. The preoperative variables were used as predictors in the multivariate logistic regression models to predict the rate of TZ PCa at RP. PCa was defined as a TZ tumor when more than 50% of the planimetrically measured tumor volume was situated within the TZ. Regression coefficients were used to develop nomograms, which were subjected to 200 bootstrap resamples to reduce overfit bias.
  
  
  RESULTS
  TZ PCa at the final pathologic examination was recorded in 110 patients (11.6%). After 200 bootstraps, the most parsimonious and most accurate nomogram was 77.3% accurate in predicting the probability of TZ PCa.
  
  
  CONCLUSIONS
  This nomogram is ideally suited to identify patients with markedly elevated, nearly metastatic serum PSA levels who harbor a TZ tumor that is highly treatable by RP.
authors.affiliation: Department of Urology, University of Hamburg, Hamburg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Steuber
authors.forename: Felix K-H
authors.initials: FK
authors.lastname: Chun
authors.forename: Andreas
authors.initials: A
authors.lastname: Erbersdobler
authors.forename: Alberto
authors.initials: A
authors.lastname: Briganti
authors.forename: Alexander
authors.initials: A
authors.lastname: Haese
authors.forename: Markus
authors.initials: M
authors.lastname: Graefen
authors.forename: Thorsten
authors.initials: T
authors.lastname: Schlomm
authors.forename: Luc
authors.initials: L
authors.lastname: Valiquette
authors.forename: Hartwig
authors.initials: H
authors.lastname: Huland
authors.forename: Pierre I
authors.initials: PI
authors.lastname: Karakiewicz
mesh_terms: D000328:Adult; D000368:Aged; D001707:Biopsy, Needle; D019160:Endosonography; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging / Q000592:standards; D049451:Nomograms; D011300:Preoperative Care; D011379:Prognosis; D011468:Prostatectomy; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D012189:Retrospective Studies; D012720:Severity of Illness Index