Ethnic differences in the age-related distribution of serum prostate-specific antigen values: A study in a healthy Korean male population

Objectives. To further improve the use of prostate-specific antigen (PSA) a s a screening test for prostate cancer in Asian countries, we sought to est ablish the normal distribution of serum PSA values in Korean men, because, until recently, studies conducted to establish normal serum PSA values have involved few Asian populations. Methods. Between May 1995 and June 1997, 5805 healthy Korean men 30 to 79 y ears old who visited our hospital for a routine health checkup were entered into a prospective study of early screening for prostate cancer. All men u nderwent detailed clinical examinations, including a digital rectal examina tion and serum PSA determination. All men who were more than 50 years old w ith abnormal digital rectal examination findings and/or an elevated serum P SA level (greater than 4.0 ng/mL) also underwent transrectal ultrasound-gui ded sextant biopsy. Four were found to have cancer and were excluded from t he analysis. Results. The median serum PSA concentration (5th to 95th percentile range) was 0.8 ng/mL (0.2 to 1.8) for patients 30 to 39 years old (n = 1382); 0.8 ng/mL (0.2 to 2.0) for patients 40 to 49 years old (n = 1776); 0.9 ng/mL (0 .2 to 2.4) for those 50 to 59 years old (n = 1775); 1.0 ng/mL (0.2 to 3.9) for men 60 to 69 years old (n = 746); and 1.3 ng/mL (0.5 to 6.3) for patien ts 70 to 79 years old (n = 122). The serum PSA concentration correlated wit h age (P <0.001), with an increase by approximately 1.2% annually, although the statistical correlation was weak (r = 0.16). Almost no change occurred in the median serum PSA value in patients 50 years old or younger; a gradu al increase was observed in patients older than 50. In those 50 years old o r older, the median and 95th percentile serum PSA values for Korean men wer e lower than those for white men. Conclusions. Contrary to earlier observations that the serum PSA level stro ngly correlates with age, the influence of age on serum PSA was found to be weaker in this study. Moreover, the results also demonstrated that the dis tribution of the serum PSA level differs along ethnic lines. The cutoff val ue for serum PSA in mass screening for prostate cancer should be adjusted i n nonwhite races. UROLOGY 56: 1007-1010, 2000. (C) 2000, Elsevier Science I nc.