Login to Access Video or Poster Abstract: MP33-07
Sources of Funding: None

Introduction

In patients with biochemical recurrence (BCR) after radical prostatectomy (RP), MRI is being increasingly utilized as the modality to visualize local recurrence. We aim to identify the role of MR-targeted biopsy to detect local recurrence in patients with rising PSA after RP. In addition, we evaluated clinical and pathologic characteristics to predict local recurrence using MR-targeted biopsy.

Methods

In a retrospective study, we identified men with rising PSA who underwent MR-targeted biopsy for local recurrence between June 2012 and June 2016. We collected data on RP pathology, pre-RP PSA, and MRI-assessed suspicion for prostate cancer scored on a standardized 5-point scale. The detection rate of prostate cancer was estimated for different MRI levels of suspicion and all patients underwent an MR-targeted biopsy. In addition, using Wilcoxon rank sum test, and Fisher’s exact test, we investigated whether RP pathologic characteristics were predictive of prostate cancer on biopsy.

Results

A total of 54 post-RP patients underwent MR-targeted biopsy for rising PSA. 25 (46%) patients had a positive biopsy identifying prostate cancer and 29 (54%) had a negative biopsy. In Table 1, MRI lesion score was the only clinical variable that was significantly associated (p=0.010) with improved detection of prostate cancer on biopsy. Additionally, subsequent increases in the MRI lesion score resulted in improved detection rates of prostate cancer. RP pathology features were not associated with biopsy outcomes (all p?077).

Conclusions

MRI-targeted biopsy can identify local recurrence in men with rising PSA after RP. The MRI lesion score is significantly associated with an increased detection rate of prostate cancer on MR-targeted biopsy, and is the only factor associated with biopsy outcomes. Our results suggest that there may be a subset of men with low MRI scores who may be precluded from biopsy, but our sample size is small and requires larger studies for confirmation.

Funding

None