To investigate the relationship of serum prostate-specific antigen (PSA) levels with outcomes of prostate needle biopsy in men 50 or more years old.

We measured serum PSA levels in 1472 healthy men 50 or more years old. Men who had serum PSA values 4.0ng/mL or higher underwent digital rectal examination. If there were either an elevated PSA level (≥4ng/mL) or abnormal digital rectal examination, a transrectal ultrasound-guided prostate biopsy was performed.

The mean serum total PSA level was 13.73±11.44ng/mL, and the mean serum free PSA level was 4.99±0.97ng/mL. Of the 260 men who had serum total PSA levels of≥4ng/mL, 139 underwent biopsy. Of these 139 men, 45 (32.4%) had prostate cancer. Benign prostatic hyperplasia with or without prostatitis was diagnosed in 94 patients (67.6%). There was no significant correlation between age and histologic results of prostate needle biopsy (P-value=0.469). The serum free PSA showed no significant correlation with histologic results of prostate needle biopsy, whereas the serum total PSA level had a significant correlation in patients with adenocarcinoma compared with other diagnosis.

The overall frequency of detection of prostate adenocarcinoma was 32.4%. This study revealed that no level of PSA was associated with a 100% positive predictive value and negative biopsy can occur virtually at any PSA level. There is a need to create awareness among the general population and health professionals for an early diagnosis of this common form of cancer.