title: A simple and accurate model for prediction of cancer-specific mortality in patients treated with surgery for primary penile squamous cell carcinoma.
abstract: OBJECTIVE
  Cancer-specific mortality (CSM) of patients with primary penile squamous cell carcinoma (PPSCC) may be quite variable. Recently, a nomogram was developed to provide standardized and individualized mortality predictions. Unfortunately, it relies on a large number (n = 8) of specific variables that are unavailable in routine clinical practice. We attempted to develop a simpler prediction rule with at least equal accuracy in predicting CSM after surgical removal of PPSCC.
  
  
  METHODS
  The predictive rule was developed on a cohort of 856 patients identified in the 1988 to 2004 Surveillance, Epidemiology and End Results (SEER) database. The predictors consisted of age, race, SEER stage (localized versus regional versus metastatic), tumor grade, type of surgery (excisional biopsy, partial penectomy, and radical penectomy), and of lymph node status (pN0 versus pN1-3 versus pNx). A look-up table based on Cox regression model-derived coefficients was used for prediction of 5-year CSM. The predictive rule accuracy was tested using the Harrell's modification of the area under the receiver operating characteristics curve.
  
  
  RESULTS
  SEER stage and histologic grade achieved independent predictor status and qualified for inclusion in the model. The model achieved 73.8% accuracy for prediction of CSM at 5 years after surgery. Both predictors achieved independent predictor status in competing risk regression models addressing CSM, where other cause mortality was controlled for.
  
  
  CONCLUSIONS
  Despite equivalent accuracy, our predictive rule predicting 5-year CSM in patients with PPSCC is substantially less complex (2 versus 8 variables) than the previously published model.
authors.affiliation: Cancer Prognostics and Health Outcomes Unit, University of Montreal Health Center, Montreal, QC, Canada.
authors.forename: Laurent
authors.initials: L
authors.lastname: Zini
authors.forename: Vincent
authors.initials: V
authors.lastname: Cloutier
authors.forename: Hendrik
authors.initials: H
authors.lastname: Isbarn
authors.forename: Paul
authors.initials: P
authors.lastname: Perrotte
authors.forename: Umberto
authors.initials: U
authors.lastname: Capitanio
authors.forename: Claudio
authors.initials: C
authors.lastname: Jeldres
authors.forename: Shahrokh F
authors.initials: SF
authors.lastname: Shariat
authors.forename: Fred
authors.initials: F
authors.lastname: Saad
authors.forename: Philippe
authors.initials: P
authors.lastname: Arjane
authors.forename: Alain
authors.initials: A
authors.lastname: Duclos
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Lattouf
authors.forename: Francesco
authors.initials: F
authors.lastname: Montorsi
authors.forename: Pierre I
authors.initials: PI
authors.lastname: Karakiewicz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002294:Carcinoma, Squamous Cell / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D006801:Humans; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D010412:Penile Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery; D011379:Prognosis