title: Patients with distant metastases from renal cell carcinoma can be accurately identified: external validation of a new nomogram.
abstract: OBJECTIVE
  To identify clinical variables that can accurately predict the presence of distant metastases in patients with renal cell carcinoma (RCC).
  
  
  METHODS
  Age, symptom classification, tumour size and the prevalence of distant metastases at diagnosis before nephrectomy were available for 5376 patients with pathologically confirmed RCC. The data of 2660 (49.5%) patients from 11 centres were used to develop a multivariable logistic regression model-based nomogram predicting the individual probability of distant metastases. The remaining data from 2716 (50.5%) patients from three institutions were used for external validation.
  
  
  RESULTS
  In the development cohort, 269/2660 (10.1%) had distant metastases, vs 285/2716 (10.5%) in the external validation cohort. Symptom classification and tumour size were independent predictors of distant metastases in the development cohort; age was not an independent predictor. A nomogram based on symptom classification and tumour size was 85.2% accurate in predicting the individual probability of distant metastases in the external validation cohort.
  
  
  CONCLUSIONS
  Although distant metastases might be easily identifiable in some patients, their diagnosis might be a challenge in others. The current nomogram provides a simple, user-friendly and, most importantly, an accurate tool aimed at predicting the probability of distant metastases in patients with RCC.
authors.affiliation: Cancer Prognostics and Health Outcomes Unit, University of Montreal Health Center, Montreal, Quebec, Canada.
authors.forename: Georg C
authors.initials: GC
authors.lastname: Hutterer
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Patard
authors.forename: Claudio
authors.initials: C
authors.lastname: Jeldres
authors.forename: Paul
authors.initials: P
authors.lastname: Perrotte
authors.forename: Alexandre
authors.initials: A
authors.lastname: de La Taille
authors.forename: Laurent
authors.initials: L
authors.lastname: Salomon
authors.forename: Gregory
authors.initials: G
authors.lastname: Verhoest
authors.forename: Jacques
authors.initials: J
authors.lastname: Tostain
authors.forename: Luca
authors.initials: L
authors.lastname: Cindolo
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Ficarra
authors.forename: Walter
authors.initials: W
authors.lastname: Artibani
authors.forename: Luigi
authors.initials: L
authors.lastname: Schips
authors.forename: Richard
authors.initials: R
authors.lastname: Zigeuner
authors.forename: Peter F
authors.initials: PF
authors.lastname: Mulders
authors.forename: Pierre I
authors.initials: PI
authors.lastname: Karakiewicz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000473:pathology* / Q000601:surgery; D015331:Cohort Studies; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008875:Middle Aged; D015999:Multivariate Analysis; D009367:Neoplasm Staging; D009392:Nephrectomy; D049451:Nomograms; D012189:Retrospective Studies; D012307:Risk Factors