Login to Access Video or Poster Abstract: MP18-01
Sources of Funding: The author&[prime]s postdoctoral fellowship is funded by a research grant from the &[Prime]Dr. Mildred Scheel&[Prime] foundation (Bonn, Germany).

Introduction

Transrectal ultrasound/magnetic resonance imaging fusion-guided biopsy (FB) of the prostate improves detection of clinically significant prostate cancer (CS PCa) compared to standard 12-core systematic biopsy (SB). However, it is still unclear which patient population benefits from FB rather than SB alone. Our goal was to determine prostate specific antigen (PSA) and PSA density (PSAD) thresholds at which FB outperforms SB.

Methods

1226 patients underwent prostate multiparametric MRI (mpMRI) including T2 weighted, diffusion weighted, apparent diffusion coefficient maps, high b value (1500-2000s/mm2) and dynamic contrast enhancement sequences from May 2015 to August 2016. Lesions were assigned suspicion scores according to the Prostate Imaging-Reporting and Data System version 2 (PI-RADSv2). PI-RADSv2 lesions scored ≥ 3 were routinely biopsied. 362/1226 patients underwent FB and SB in the same session. The highest Gleason scores detected by FB and SB were determined on a patient level. Patients who were upgraded to CS PCa (≥Gleason score of 3+4) by FB over SB and vice versa were identified. By calculating cumulative PSA and PSAD curves, exact thresholds for PSA and PSAD were determined at which FB upgraded more patients to CS PCa compared to SB.

Results

167/362 patients were diagnosed with CS PCa. 55 patients were upgraded by FB, 35 were upgraded by SB, and both modalities diagnosed CS PCa in 77 patients. Thresholds of 6.15ng/ml for PSA and 0.14 for PSAD were determined (Figure 1).

Conclusions

Patients with a PSA ≥ 6.15ng/ml or a PSAD ≥ 0.14 appear to benefit more from mpMRI and subsequent FB if suspicious lesions are detected on mpMRI than patients with values below these thresholds.

Funding

The author&[prime]s postdoctoral fellowship is funded by a research grant from the &[Prime]Dr. Mildred Scheel&[Prime] foundation (Bonn, Germany).