Introduction

Prostate mpMRI guided biopsies improve detection of Gleason score ?7cancer (PCa). The objective of the current study is to assess diagnostic reliability in comparison to definitive histological diagnosis. We present a retrospective analysis of our detection accuracy of PCa by mpMRI and TPFB in comparison to histological specimens from Robotic-Assisted Radical Prostatectomy (RARP).

Methods

1002 men have had TPFB at Cambridge University Hospitals Trust between March 2012 and April 2016. 93 have subsequently undergone RARP for PCa. mpMRI was performed on all 93 patients and reported according to PIRADSvs2. 79/93 (84.9%) patients had ?1 mpMRI lesions with Likert score > 2 (Likert 3=11; Likert 4=27; Likert 5=41). TPFB was performed on each patient. 2-4 samples were taken from the target zone identified on mpMRI (TB) and 18-24 samples systematically taken according to Ginsburg protocol (SB). 14/93 had a negative mpMRI but were diagnosed with PCa following SB. Samples were retrospectively compared to RARP histology. Data was examined for overall detection rate of PCa and histological analysis of each Likert group (5,4,3), TB, SB and RARP samples according to Gleason score. Results determined diagnostic accuracy of biopsy samples in comparison to definitive histological diagnosis.

Results

67/79 (84.1%) patients had TB positive for PCa, with a second lesion positive in 17/79 cases. Gleason score of TB and SB was equivalent in 29 (36.7%). Gleason score was higher in TB and SB in 15 (19%) and 35 (44%) cases, respectively. TB was benign in 14 patients. Gleason score at biopsy and RARP were equivalent in 49 (52.7%) cases but higher in RARP and biopsy in 10 and 34 cases, respectively. TB was PCa positive in 38/41 (92.7%) Likert 5 lesions. 2/3 remaining patients had PCa positive SB in an identical region to TB. 21/27 (77.8%) Likert 4 lesions had TB positive PCa, 3/6 remaining cases had PCa positive SB in an identical region to TB. TB was positive in 9/11 (81.8%) of Likert 3 lesions with SB negative in the remaining 2 patients. The correlation between mpMRI-TPFB-RARP was positive for 97.6% Likert 5, 88.9% Likert 4 and 85.7% Likert 3 lesions. mpMRI identified a suspicious lesion confirmed on RARP in 74 patients (93.7%). 2/5 patients with a negative correlation had a second MRI lesion that corresponded to RARP.

Conclusions

The results of our analysis demonstrate the accuracy of mpMRI and the reliability of TB taken during TPFB in confirming PCa when compared to SB and definitive histological diagnosis.

Funding

none