title: Head-to-head comparison of two online nomograms for prostate biopsy outcome prediction.
abstract: METHODS
  Diagnosis (exploratory cohort).
  
  
  METHODS
  2b. What's known on the subject? and What does the study add? In recent years, several nomograms were developed in an effort to decrease the number of unnecessary prostate biopsies. The European SWOP-PRI and the North American PCPT are among the most popular. However, evidence on the relative predictive accuracy is lacking. A head-to-head comparison on the diagnostic accuracy of two previously validated prostate cancer risk predictors on biopsy confirmed the superiority of these tools over PSA alone. Moreover, in the studied population, the European SWOP-PRI proved to be more accurate than the North American PCPT-CRC.
  
  
  OBJECTIVE
  To compare the diagnostic accuracy of two previously validated prostate cancer risk predictors on biopsy.
  
  
  METHODS
  In total, 390 consecutive patients submitted to 10-core systematic transrectal prostate biopsy at our institution were included in this retrospective study. External validation of a European (European Randomized Study of Screening for Prostate Cancer derived Prostate Risk Indicator; SWOP-PRI) and a North American (Prostate Cancer Prevention Trial Cancer Risk Calculator; PCPT-CRC) nomogram was performed. The predictive accuracy of these online available nomograms was calculated based on the area under the curve derived from receiver-operator characteristic curves and then compared using the DeLong method.
  
  
  RESULTS
  Both tools were confirmed to be superior to prostate-specific antigen alone. Moreover, the SWOP-PRI (77.9%) displays a 7.96% increase in the predictive accuracy compared to the PCPT-CRC (69.9%) in a statistically significant fashion (P=0.002).
  
  
  CONCLUSIONS
  The results obtained in the present study confirm the utility of nomograms with respect to biopsy outcome prediction in patients with suspicion of prostate cancer. In the current sample of patients, the European-based nomogram appears to be more accurate than the North American nonogram, which lacks information regarding prostate volume and prostatic ultrasonographic lesions. • To our knowledge, this is the first study to compare the accuracy of these popular risk calculators in a specific population.
authors.affiliation: Department of Urology, Hospital de Braga, Braga, Portugal. mariooliveira@ecsaude.uminho.pt
authors.forename: Mário
authors.initials: M
authors.lastname: Oliveira
authors.forename: Vera
authors.initials: V
authors.lastname: Marques
authors.forename: António Pedro
authors.initials: AP
authors.lastname: Carvalho
authors.forename: Américo
authors.initials: A
authors.lastname: Santos
mesh_terms: D000367:Age Factors; D000368:Aged; D001707:Biopsy, Needle / Q000592:standards*; D015331:Cohort Studies; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000473:pathology; D049451:Nomograms; D011237:Predictive Value of Tests; D011379:Prognosis; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000473:pathology*; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D018084:Ultrasonography, Interventional
chemical_list: D017430:Prostate-Specific Antigen