title: Rule-based versus probabilistic selection for active surveillance using three definitions of insignificant prostate cancer.
abstract: OBJECTIVE
  To study whether probabilistic selection by the use of a nomogram could improve patient selection for active surveillance (AS) compared to the various sets of rule-based AS inclusion criteria currently used.
  
  
  METHODS
  We studied Dutch and Swedish patients participating in the European Randomized study of Screening for Prostate Cancer (ERSPC). We explored which men who were initially diagnosed with cT1-2, Gleason 6 (Gleason pattern ≤3 + 3) had histopathological indolent PCa at RP [defined as pT2, Gleason pattern ≤3 and tumour volume (TV) ≤0.5 or TV ≤ 1.3 ml, and TV no part of criteria (NoTV)]. Rule-based selection was according to the Prostate cancer Research International: Active Surveillance (PRIAS), Klotz, and Johns Hopkins criteria. An existing nomogram to define probability-based selection for AS was refitted for the TV1.3 and NoTV indolent PCa definitions.
  
  
  RESULTS
  619 of 864 men undergoing RP had cT1-2, Gleason 6 disease at diagnosis and were analysed. Median follow-up was 8.9 years. 229 (37%), 356 (58%), and 410 (66%) fulfilled the TV0.5, TV1.3, and NoTV indolent PCa criteria at RP. Discriminating between indolent and significant disease according to area under the curve (AUC) was: TV0.5: 0.658 (PRIAS), 0.523 (Klotz), 0.642 (Hopkins), 0.685 (nomogram). TV1.3: 0.630 (PRIAS), 0.550 (Klotz), 0.615 (Hopkins), 0.646 (nomogram). NoTV: 0.603 (PRIAS), 0.530 (Klotz), 0.589 (Hopkins), 0.608 (nomogram).
  
  
  CONCLUSIONS
  The performance of a nomogram, the Johns Hopkins, and PRIAS rule-based criteria are comparable. Because the nomogram allows individual trade-offs, it could be a good alternative to rigid rule-based criteria.
authors.affiliation: Department of Urology, Erasmus University Medical Center, Room Na1710, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands. l.venderbos@erasmusmc.nl.|Department of Public Health, Erasmus University Medical Center, Rotterdam, The Netherlands. l.venderbos@erasmusmc.nl.
authors.forename: Lionne D F
authors.initials: LD
authors.lastname: Venderbos
authors.affiliation: Department of Urology, Erasmus University Medical Center, Room Na1710, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands.
authors.forename: Monique J
authors.initials: MJ
authors.lastname: Roobol
authors.affiliation: Department of Urology, Erasmus University Medical Center, Room Na1710, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands.
authors.forename: Chris H
authors.initials: CH
authors.lastname: Bangma
authors.affiliation: Department of Urology, Erasmus University Medical Center, Room Na1710, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands.
authors.forename: Roderick C N
authors.initials: RC
authors.lastname: van den Bergh
authors.affiliation: Department of Urology, Erasmus University Medical Center, Room Na1710, P.O. Box 2040, 3000 CA, Rotterdam, The Netherlands.
authors.forename: Leonard P
authors.initials: LP
authors.lastname: Bokhorst
authors.affiliation: Department of Public Health, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Daan
authors.initials: D
authors.lastname: Nieboer
authors.affiliation: Department of Urology, Sahlgrenska Academy at Göteborg University, Göteborg, Sweden.
authors.forename: Rebecka
authors.initials: R
authors.lastname: Godtman
authors.affiliation: Department of Urology, Sahlgrenska Academy at Göteborg University, Göteborg, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Hugosson
authors.affiliation: Department of Pathology, Toronto General Hospital, University Health Network, Toronto, Canada.
authors.forename: Theodorus
authors.initials: T
authors.lastname: van der Kwast
authors.affiliation: Department of Public Health, Erasmus University Medical Center, Rotterdam, The Netherlands.
authors.forename: Ewout W
authors.initials: EW
authors.lastname: Steyerberg
mesh_terms: D005060:Europe / Q000453:epidemiology; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009017:Morbidity / Q000639:trends; D009367:Neoplasm Staging / Q000379:methods*; D049451:Nomograms; D018579:Patient Selection; D011467:Prostate / Q000473:pathology*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000453:epidemiology; D018570:Risk Assessment / Q000379:methods*; D015996:Survival Rate / Q000639:trends; D013997:Time Factors; D047368:Tumor Burden; D057832:Watchful Waiting
keywords: Active surveillance; Inclusion criteria active surveillance; Nomogram; Prostatic neoplasm; Risk stratification; Selection for active surveillance