Genetically adjusted prostate-specific antigen values may prevent delayed biopsies in African-American men.
OBJECTIVE
To evaluate whether genetic correction using the genetic variants prostate-specific antigen (PSA)-single nucleotide polymorphisms (SNPs) could reduce potentially unnecessary and/or delayed biopsies in African-American men.


METHODS
We compared the genotypes of four PSA-SNPs between 964 Caucasian and 363 African-American men without known prostate cancer (PCa). We adjusted the PSA values based on an individual's PSA-SNP carrier status, and calculated the percentage of men that would meet commonly used PSA thresholds for biopsy (≥ 2.5 or ≥ 4.0 ng/mL) before and after genetic correction. Potentially unnecessary and delayed biopsies were defined as those men who were below and above the biopsy threshold after genetic correction, respectively.


RESULTS
Overall, 349 (96.1%) and 354 (97.5%) African-American men had measured PSA levels <2.5 and <4.0 ng/mL. Genetic correction in African-American men did not avoid any potentially unnecessary biopsies, but resulted in a significant (P < 0.001) reduction in potentially delayed biopsies by 2.5% and 3.9%, based on the biopsy threshold level.


CONCLUSIONS
There are significant differences in the influence of the PSA-SNPs between African-American and Caucasian men without known PCa, as genetic correction resulted in an increased proportion of African-American men crossing the threshold for biopsy. These results raise the question of whether genetic differences in PSA might contribute to delayed PCa diagnosis in African-American men.
Department of Urology, New York University Langone Medical Center and Manhattan Veterans Affairs Medical Center, New York, NY, USA.
Nicholas M
NM
Donin
Department of Urology, New York University Langone Medical Center and Manhattan Veterans Affairs Medical Center, New York, NY, USA.
Stacy
S
Loeb
Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
Phillip R
PR
Cooper
Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
Kimberly A
KA
Roehl
Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
Nikola A
NA
Baumann
Department of Urology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
William J
WJ
Catalona
Division of Urology, NorthShore University Healthcare System, Evanston, IL, USA.
Brian T
BT
Helfand
D001741:Black or African American / Q000235:genetics*; D000368:Aged; D057210:Delayed Diagnosis / Q000517:prevention & control*; D055088:Early Detection of Cancer; D061765:Endoscopic Ultrasound-Guided Fine Needle Aspiration / Q000706:statistics & numerical data*; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D017430:Prostate-Specific Antigen / Q000097:blood / Q000235:genetics*; D011471:Prostatic Neoplasms / Q000235:genetics* / Q000473:pathology; D019564:Unnecessary Procedures; D044465:White People / Q000235:genetics*
D017430:Prostate-Specific Antigen
African-American; PSA; genetic variants; prostate cancer; single nucleotide polymorphism