Prostate cancer risk prediction in a urology clinic in Mexico.
OBJECTIVE
To evaluate factors affecting the risk of prostate cancer (CaP) and high-grade disease (HGCaP, Gleason score ≥ 7) in a Mexican referral population, with comparison to the Prostate Cancer Prevention Trial Prostate Cancer Risk Calculator (PCPTRC).


METHODS
From a retrospective study of 826 patients who underwent prostate biopsy between January 2005 and December 2009 at the Instituto Nacional de Cancerología, Mexico, logistic regression was used to assess the effects of age, prostate-specific antigen (PSA), digital rectal exam (DRE), first-degree family history of CaP, and history of a prior prostate biopsy on CaP and HGCaP, separately. Internal discrimination, goodness-of-fit, and clinical utility of the resulting models were assessed with comparison to the PCPTRC.


RESULTS
Rates of both CaP (73.2%) and HGCaP (33.3%) were high among referral patients in this Mexican urology clinic. The PCPTRC generally underestimated the risk of CaP but overestimated the risk of HGCaP. Four factors influencing CaP on biopsy were logPSA, DRE, family history and a prior biopsy history (all P < 0.001). The internal AUC of the logistic model was 0.823 compared with 0.785 of the PCPTRC for CaP (P < 0.001). The same 4 factors were significantly associated with HGCaP as well and the AUC was 0.779 compared with 0.766 of the PCPTRC for HGCaP (P = 0.13).


CONCLUSIONS
Lack of screening programs or regular urologic checkups in Mexico imply that men typically first reach specialized clinics with a high cancer risk. This renders diagnostic tools developed on comparatively healthy populations, such as the PCPTRC, of lesser utility. Continued efforts are needed to develop and externally validate new clinical diagnostic tools specific to high-risk referral populations incorporating new biomarkers and more clinical characteristics.
Department of Epidemiology and Biostatistics, University of Texas Health Science Center at San Antonio (UTHSCSA), San Antonio, TX 78229, USA; Department of Urology, UTHSCSA, San Antonio, TX 78229, USA; School of Public Health, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; Cancer Therapy and Research Center, UTHSCSA, San Antonio, TX 78229, USA. Electronic address: liangy@uthscsa.edu.
Yuanyuan
Y
Liang
Jamie C
JC
Messer
Christopher
C
Louden
Miguel A
MA
Jimenez-Rios
Ian M
IM
Thompson
Hector R
HR
Camarena-Reynoso
D000368:Aged; D000554:Ambulatory Care Facilities / Q000706:statistics & numerical data*; D001706:Biopsy; D051517:Digital Rectal Examination; D005192:Family Health; D006801:Humans; D016015:Logistic Models; D008297:Male; D008800:Mexico; D008875:Middle Aged; D060787:Neoplasm Grading; D011379:Prognosis; D011467:Prostate / Q000473:pathology*; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000517:prevention & control; D012017:Referral and Consultation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D014572:Urology
D017430:Prostate-Specific Antigen