RELATIONSHIP BETWEEN PROSTATE-SPECIFIC ANTIGEN AND PROSTATE VOLUME IN KOREAN MEN WITH BENIGN PROSTATIC HYPERPLASIA FROM MULTICENTER STUDY

초록

INTRODUCTION AND OBJECTIVE: Prostate volume (PV) is a key predictor of both progression and response to medical therapy in patients with benign prostatic hyperplasia (BPH). Prostate specific antigen (PSA) has been studied as a proxy marker to estimate the total prostate volume in a predominantly Caucasian patient population. If PV of Korean men is smaller than that of Caucasian men, the PSA-PV may be different for Korean men from other races. We evaluated the relationship between PSA and PV in Korean men. METHODS: Patients with lower urinary tract symptoms and BPH aged between 50 and 79 years, were enrolled in the multicenter study from 1999 to 2004. IPSS, PSA, uroflometry and TRUS measurements were performed on all patients. Men with PSA greater than 10 ng/mL were excluded to reduce the likelihood of including occult prostate cancer cases. Those with suspicious findings in digital rectal examination and serum PSA were biopsied to rule out prostate cancer. RESULT: The analysis included 5,716 patients with a mean age 64.3 years, mean baseline PV 36.9 ml, and baseline PSA value 2.4 ng/mL. PV and serum PSA have an age-dependent log-linear relationship. Older men tend to have a steeper rate of increase in PV with increasing serum PSA. Receiver operating characteristic (ROC) curves were constructed to evaluate the ability of serum PSA to predict threshold PV in men with BPH. The ROC curve analysis revealed that PSA had good predictive value for various prostate volume cutoff points (30, 35, 40, 45, and 50 mL). CONCLUSIONS. The PSA-PV relationship in Korean men is similar to Caucasians. However, Korean men have lower PSA and smaller PV than Caucasians. For Korean men, the PV of greater than 35 mL may be optimal cutpoint to predict response to 5 alpha reductase inhibitors. Approximate age-sepcific criteria for detecting Korean men with PV exceeding 35 mL are PSA >1.2 ng/mL, >1.6 ng/mL, and >2.0 ng/mL for men with BPH in their 50s, 60s, and 70s, respectively.