Prostate cancer diagnosis: should patients with prostate specific antigen >10 ng/mL have stratified prostate biopsy protocols?

Abstract

Background: Trans-rectal ultrasound (TRUS) guided systematic prostate biopsy is a standard tool in prostate cancer (CaP) diagnosis. Extended biopsy techniques using 10–12 cores are the norm. Controversy exists on extended TRUS biopsy in men with PSA >10 ng/mL. We evaluated cancer detection rates on an individual core basis, to stratify prostate biopsy protocols based on PSA levels. Patients and methods: Over a five-year period, 1036 patients underwent TRUS guided prostate biopsy for raised serum PSA (>2.5 ng/mL). 436 patients had PSA >10 ng/mL. Patients with PSA <50 ng/mL underwent a 12-core TRUS guided prostate biopsy including six peripheral biopsies. The six peripheral biopsies were directed laterally towards the base, mid-zone and apices. Remainder were standard para-sagittal sextant biopsies. Patients were stratified into three groups (PSA 10–20 ng/mL, 20–50 ng/mL and >50 ng/mL). Results: Mean age of 436 patients with PSA >10 ng/mL was 70.3years. 270 (62%) men had cancer. Cancer detection rates for different PSA levels were 46% (10–20 ng/mL), 76% (20–50 ng/mL) and 93% (>50 ng/mL). Higher PSA levels and advanced clinical stage were associated with increased cancer detection rates. All patients with clinical T3 and T4 disease had biopsy diagnosed CaP. Conclusion: TRUS guided prostate biopsy in patients with PSA >10 ng/mL did not require 12 cores to diagnose CaP. CaP diagnosis required 8 cores in men with PSA 10–20 ng/mL. These cores were right and left peripheral basal and apical, and right and left para-sagittal basal and apical biopsy. Only 6 cores were necessary to diagnose CaP in men with PSA >20 ng/mL which were right and left peripheral basal and apical, and para-sagittal apical biopsies. We suggest limited TRUS prostate biopsy protocols for men with PSA >10 ng/mL.