Validity of digital rectal examination and serum prostate specific antigen in the estimation of prostate volume in community-based men aged 50 to 78 years: the Krimpen Study.

BACKGROUND: In men with symptoms suggestive of BPH, an accurate estimation of the degree of prostate volume enlargement is important for the choice of treatment, and for prediction of treatment effect, the risk of acute urinary retention and the need for surgery. In a community-based population of men, the performance of digital rectal examination (DRE) and serum prostate specific antigen (PSA) is compared to planimetric transrectal ultrasonometry (planimetric TRUS) of the prostate. In this way we search for a practical, reliable, and reproducible alternative to TRUS that can be applied in a primary care setting and in the initial evaluation of men with lower urinary tract symptoms.
METHODS: Data were collected from 1688 men aged 50 to 78 years recruited in a population-based study. Measurements included serum PSA, DRE, and planimetric TRUS for the estimation of prostate volume.
RESULTS: The AUC values of the receiver-operating curves (ROC) curves for serum PSA as a method for the discrimination of prostate volumes above or below 30, 40 and 50 cc are 0.79, 0.86 and 0.92, respectively. DRE has limited value in the estimation of prostate volume and is only good in identifying very large prostates (>50 cc).
CONCLUSIONS: In the general male population serum PSA performs reasonably well compared with planimetric TRUS, and better than DRE, in estimating whether prostate volume is greater or smaller than 30, 40 or 50 cc. Serum PSA is an acceptable alternative method to estimate the degree of prostatic enlargement in clinical settings where TRUS is not available and when prostate cancer has been excluded.