Abstract
Objectives: This multicentric clinical study was initiated to check whether percent free PSA, PSA density (PSAD) and PSA density of the transition zone (TZ-PSAD) could enhance the specificity of total PSA alone without reducing its sensitivity in the diagnosis of clinical T1c prostate cancer by ultrasonically guided transrectal sextant biopsies in patients with a total PSA between 3 and 15 ng/ml.
Patients and methods: A total of 306 patients were evaluated in seven different centres in the Netherlands and Belgium over a 2-year period. Patients with intermediate PSA levels (3.0–15 ng/ml) underwent measurement of prostate volume by transrectal ultrasound (TRUS) and sextant biopsy under TRUS guidance. The PSAD, TZ-PSAD and percent free PSA were determined for each patient, and their relationship to prostate cancer detection was examined.
Results: Identical receiver operating characteristic (ROC) curves for PSAD and TZ-PSAD could be constructed. ROC analysis showed that percent free PSA was inferior to total PSA, PSAD and TZ-PSAD in the detection of prostate cancer.
Conclusion: PSAD, TZ-PSAD and percent free PSA do not enhance the specificity of total PSA for cancer detection in men with PSA values between 3 and 15 ng/ml. Each centre has to use his preferential PSA-modification.