Serum PSA concentration, Prostate Specific Antigen Density with Aging

Chung, Byung Ha; Hong, Sung Joon; Lee, Seung Eon; Lee, Dong Hyun

Abstract

By definition, PSAD is the serum PSA concentration divided volume of the gland, as determined from transrectal ultrasonography. If prostatic volume were the sole determinant of the serum PSA concentration, there would be no correlation between PSAD and age. We examined the relationships between serum PSA concentration, rostatic volume and age. Entry included 318 men over 40 years who have no clinical evidence of prostate cancer. The mean age of this study population was 65.2(range 40-89). The mean PSA was 3.94ng/ml and the mean prostate volume 36.4cc(range 11-120). 85 men(26.7 %) had volumes >20cc and levels >4ng/ml. When all entry included, the serum PSA concentration correlates directly with age (r=0.2, p<0.01). Based on linear regression analysis, the serum PSA concentration would increase approximately 2.7% per year. The prostatic volume correlates directly with age(r=0.3, p<0.01). Based on linear regression analysis, the prostatic volume would increase approximately 2.2% per year. Correlation between the prostatic volume and PSA was also significant(r=0.1, p<0.01). Based on linear regression analysis, an increase in prostatic volume of 1mL will, on the average, produce a corresponding increase of 3.2% in PSA. There was an increasing tendency of PSAD with age but statistically insignificant. The mean PSAD was 0.11 but 47men of 59 had >0.15 in levels 4-10ng/ml. In conclusion, the application of PSAD in clinical field should be taken into consideration seriously and interpretation of PSA should be include the corresponding variables such as age and prostate volume. The PSA velocity or age specific reference range for PSA can aid in the application of PSA.