title: External validation of a nomogram for identification of pathologically favorable disease in intermediate risk prostate cancer patients.
abstract: OBJECTIVE
  To establish an external validation of the new nomogram from Gandaglia et al which provides estimates of the probability of pathological favorable disease in pre-operatively defined intermediate-risk PCa.
  
  
  METHODS
  Overall, 2928 intermediate-risk PCa patients according to the D'Amico classification undergoing RP and bilateral lymph node dissection in seven academic centres between 2000 and 2011. Pathologically favorable PCa was defined as low-grade organ-confined disease. The Receiver Operating Characteristic (ROC) curve was obtained to quantify the overall accuracy (Area Under the Curve, AUC) of the model to predict specimen-confined (SC) disease. Calibration curve was then constructed to illustrate the relationship between the risk-estimates obtained by the model and the observed proportion of SC disease. Kaplan-Meier method was used for PSA recurrence-free survival (PSA-RFS) assessment.
  
  
  RESULTS
  Median age was 68 years. 10.6% patients finally presented pathologically favorable disease characteristics at RP. A higher PSAD (OR = 0.01; 95%CI = 0.00-0.04; P < 0.0001) and percentage of positive cores (OR = 0.97; 95%CI = 0.96-0.98; P < 0.0001) were associated with a reduced probability of favorable disease at RP in multivariate analysis. ROC curve analysis showed strongest accuracy of the model (AUC = 0.82; 95%CI = 0.79-0.84). Favorable PCa had a significantly better PSA recurrence-free survival rates as compared to unfavorable PCa after RP (94.2% vs 74.4% at 4 years, P < 0.0001).
  
  
  CONCLUSIONS
  This external validation of the Gandaglia nomogram shows relevant accuracy with one out of ten patients in this intermediate risk PCa group with pathologically proven organ-confined disease. This validated risk calculator can help physician to distinguish favorable intermediate risk PCa that can be treated by conservative approach or safer nerve-sparing surgery.
authors.affiliation: Department of Urology, Centre Hospitalier Universitaire de Toulouse, Toulouse, France.
authors.forename: Jean-Baptiste
authors.identifier: http://orcid.org/0000-0002-1532-015X
authors.initials: JB
authors.lastname: Beauval
authors.affiliation: Department of Statistics, Institut Universitaire du Cancer Toulouse Oncopole, Toulouse, France.
authors.forename: Bastien
authors.initials: B
authors.lastname: Cabarrou
authors.affiliation: Ospedale San Raffaele, Milano, Lombardia, Italy.
authors.forename: Giorgio
authors.initials: G
authors.lastname: Gandaglia
authors.affiliation: Department of Urology, Centre Hospitalier Universitaire de Toulouse, Toulouse, France.
authors.forename: Pierre-Marie
authors.initials: PM
authors.lastname: Patard
authors.affiliation: Centre Hospitalier Regional Universitaire de Lille, Lille, France.
authors.forename: Adil
authors.initials: A
authors.lastname: Ouzzane
authors.affiliation: Department of Urology, CHU Mondor, Créteil, France.
authors.forename: Alexandre
authors.initials: A
authors.lastname: de la Taille
authors.affiliation: Department of Urology, Centre Hospitalier Universitaire de Toulouse, Toulouse, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Soulié
authors.affiliation: Department of Urology, Vita-Salute University San Raffaele, Milan, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Briganti
authors.affiliation: Clinique St Jean du Languedoc, Toulouse, France.
authors.forename: Guillaume
authors.initials: G
authors.lastname: Ploussard
authors.affiliation: Institut Mutualiste Montsouris, Paris, France.
authors.forename: François
authors.identifier: http://orcid.org/0000-0001-5722-2075
authors.initials: F
authors.lastname: Rozet
authors.affiliation: Department of Urology, Centre Hospitalier Universitaire de Toulouse, Toulouse, France.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Roumiguié
mesh_terms: D000368:Aged; D006801:Humans; D008197:Lymph Node Excision / Q000009:adverse effects / Q000379:methods; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D009367:Neoplasm Staging; D049451:Nomograms; D018579:Patient Selection; D011468:Prostatectomy / Q000009:adverse effects / Q000379:methods; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000473:pathology; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors
keywords: biochemical recurrence; disease; favorable; final pathology; intermediate-risk prostate cancer; nomogram; radical prostatectomy