Prostate-Specific Antigen as an Estimator of Prostate Volume in Patients with Benign Prostatic Hyperplasia by Decade of Life

Chang, Hyuk Soo; Park, Choal Hee; Kim, Chun Il

Abstract

PURPOSE: To investigate the ability of serum prostate specific antigen (PSA) as an estimator of the prostate volume in patients with symptomatic benign prostatic hyperplasia (BPH) according to their decade of life.
MATERIALS AND METHODS
Between January 1997 and May 2003, 3,192 patients presented at our clinic due to lower urinary tract symptoms. Of these 1,922 were confirmed as BPH and enrolled in this study. Patients with prostate cancer and conditions other than BPH at the baseline were excluded. Receiver operating characteristic (ROC) curves were constructed to evaluate the diagnostic ability of serum PSA to estimate the threshold prostate volume and select the optimal PSA cut-off values.
RESULTS
The ROC curve analyses revealed the serum PSA to be a good estimator of the prostate volume, with areas under the ROC curves of 0.785, 0.846 and 0.856 for prostate volume cut-off points of 30, 40 and 50ml, respectively. The optimal serum PSA cut-off values for all age groups, irrespective of age, were 1.5ng/ml for the detection of a prostate volume>30ml and 2.0ng/ml for a prostate volume>40ml.
CONCLUSIONS
Serum PSA can be used to estimate the prostate volume. Since the treatment outcome or risk of complications depends on the prostate volume, the estimated prostate volume is useful in therapeutic decision making in the absence of a reliable direct measurement of the prostate volume.