title: The use of the finasteride-adjusted Prostate Cancer Prevention Trial Prostate Cancer Risk Calculator in a Mexican referral population: a validation study.
abstract: OBJECTIVE
  To perform the first validation study of the finasteride-adjusted Prostate Cancer Prevention Trial Prostate Cancer Risk Calculator (finPCPTRC) in a contemporary referral population in Mexico.
  
  
  METHODS
  837 patients referred to the Instituto Nacional de Cancerología, Mexico City, Mexico, between 2005 and 2009 were used to validate the finPCPTRC by examining various measures of discrimination and calibration. Net benefit curve analysis was used to gain insight into the use of the finPCPTRC for clinical decisions.
  
  
  RESULTS
  Prostate cancer (PCa) incidence (72.8%) was high in this Mexican referral cohort and 45.7% of men who were diagnosed with PCa had high-grade lesions (HGPCa, Gleason score >6). 1.3% of the patients were taking finasteride. The finPCPTRC was a superior diagnostic tool compared to prostate-specific antigen alone when discriminating patients with PCa from those without PCa (AUC = 0.784 vs. AUC = 0.687, p < 0.001) and when discriminating patients with HGPCa from those without HGPCa (AUC = 0.768 vs. AUC = 0.739, p < 0.001). The finPCPTRC underestimated the risk of PCa but overestimated the risk of HGPCa (both p < 0.001). Compared with other strategies to opt for biopsy, the net benefit would be larger with utilization of the finPCPTRC for patients accepting higher risks of HGPCa.
  
  
  CONCLUSIONS
  Rates of biopsy-detectable PCa and HGPCa were high and 1.3% of this referral cohort in Mexico was taking finasteride. The risks of PCa or HGPCa calculated by the finPCPTRC were not well calibrated for this referral Mexican population and new clinical diagnostic tools are needed.
authors.affiliation: Department of Epidemiology and Biostatistics, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA. liangy @ uthscsa.edu
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Liang
authors.forename: Norma S
authors.initials: NS
authors.lastname: Ketchum
authors.forename: Christopher
authors.initials: C
authors.lastname: Louden
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Jimenez-Rios
authors.forename: Ian M
authors.initials: IM
authors.lastname: Thompson
authors.forename: Hector R
authors.initials: HR
authors.lastname: Camarena-Reynoso
mesh_terms: D058891:5-alpha Reductase Inhibitors / Q000627:therapeutic use*; D000367:Age Factors; D000368:Aged; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D001706:Biopsy; D016009:Chi-Square Distribution; D051517:Digital Rectal Examination; D018120:Finasteride / Q000627:therapeutic use*; D020022:Genetic Predisposition to Disease; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D015999:Multivariate Analysis; D060787:Neoplasm Grading; D016017:Odds Ratio; D010375:Pedigree; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000175:diagnosis* / Q000188:drug therapy* / Q000453:epidemiology / Q000235:genetics / Q000473:pathology; D012017:Referral and Consultation; D015203:Reproducibility of Results; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors
chemical_list: D058891:5-alpha Reductase Inhibitors; D018931:Antineoplastic Agents, Hormonal; D018120:Finasteride; D017430:Prostate-Specific Antigen