Repeat transrectal ultrasound‐guided prostate biopsy for elevated PSA with prior negative biopsy, how many biopsies is enough?

Abstract

Objective:

This study aims 1) to identify the predictive factors for prostate cancer detection in repeat TRUS biopsy and 2) to illustrate the incidence of prostate cancer in repeat biopsies.

Patients and Methods:

A retrospective analysis was carried out in patients who underwent TRUS biopsy in our hospital between January 2000 to December 2013. Patient demographics, digital rectal examination finding, PSA level, prostate volume, number of biopsies and biopsy results were analysed.

Results:

682 patients underwent repeat TRUS biopsy for elevated PSA with prior negative biopsy. Multivariate analysis showed that PSA density (OR 5.107, Cl 1.31–19.9, p = 0.019) and abnormal DRE (OR 2.36, Cl 1.19–4.70, p = 0.014) were independent factors associated with malignancy in second biopsy. The cut off PSA density defined by the ROC curve is >= 0.176 ng/mL with sensitivity of 75.7% and specificity of 42.7%. In addition, the detection rate of clinically significant prostate cancer (Gleason score > 6) decreased by the fourth repeat biopsy (19.9%, 3.23%, 4.25% and 0%, from first to fourth biopsy).

Conclusion:

When patients are under PSA observation following a non‐targeted TRUS biopsy, PSA density and DRE findings should be used to guide decisions on whether the patients require a repeat biopsy.