OBJECTIVE: To investigate the prostate cancer (PCa) prevalence and risk factors of men with prostate-specific antigen (PSA) level<or =4.0 ng/ml and an unsuspicious digital rectal examination (DRE) in a large biopsy referral cohort. MATERIALS AND METHODS: Between 1997 and 2005, 855 men underwent initial transrectal ultrasound (TRUS)-guided prostate biopsy at the University Hospital Hamburg-Eppendorf. Patients with any previous surgical or medical treatment were excluded from analyses. Logistic regression analyses were performed to determine risk factors of PCa at biopsy and high-grade PCa defined as biopsy Gleason sum> or =7. RESULTS: Overall PCa detection rate was 23.1%. The majority had a biopsy Gleason sum of 6 (79.5%) and 20.5% had a biopsy Gleason sum> or =7. Total PSA (tPSA) and percentage of free PSA (%fPSA) were statistically significantly different in men with and without PCa (all p or = 7 at biopsy, %fPSA and prostate volume represented independent and most informative risk factors. CONCLUSION: Our data demonstrate that a substantial percentage (23.1%) of men with a PSA<or =4.0 ng/ml and an unsuspicious DRE in a biopsy referral population harbor PCa, with 20.5% being high grade. Low %fPSA and low prostate volume represent important parameters in PCa and in high grade disease detection at biopsy, respectively.
