Abstract: PD65-11
Sources of Funding: none

Introduction

In recent years, multi-parametric MRI (mpMRI) has gained increased acceptance and utilization as a diagnostic and staging tool for early - stage prostate cancer. Reporting systems, in particular the Prostate Imaging - Reporting and Data System (PI-RADS), now in its second version, has been advanced as means to standardize the grading and reporting of MRI findings. However, it remains to be determined whether PI-RADS scores independently predict the risk of adverse pathology, i.e. high-grade and/or high-stage disease. _x000D_ Objective: To evaluate the association of surgical pathological findings assessed on whole-mount pathology analysis and pre-operative mpMRI suspicion assessed using PI-RADS v2 scores._x000D_

Methods

We retrospectively analyzed 121 patients who had radical prostatectomy within 12 months of their staging endorectal 3T mpMRI. We examined the association of the PI-RADS v2 scores with adverse surgical pathology, defined as advanced pathologic stage (≥ pT3a) or high-grade disease (primary Gleason pattern ≥ 4) or both, using frequency tables (diagnostic accuracy and chi-square) and logistic regression models.

Results

Of 121 patients, 73 (60%) had adverse surgical pathology; 9 men (7%) had high-grade, 64 (29%) had ≥ pT3 disease, and 29 (24%) had both high-grade and high-stage disease. 106 (88%) had PI-RADS mpMRI score 4 or 5 findings, of whom, 65% had adverse pathology compared to 15 (12%) patients with PI-RADS ≤3, of whom 27% had adverse pathology. Conversely, 95% (69/73) of patients with adverse pathology had positive MR studies (PI-RADS score 4 or 5). Accordingly, mpMRI PI-RADS 4 or 5 demonstrated 95% sensitivity (95% CI 87-98), 23% specificity (95% CI 12-37), 65% PPV (95% CI 55-74), 73% NPV (95% CI 45-92), and 66% accuracy (95% CI 57-75) for the detection of adverse surgical pathology. In the multivariable logistic regression analysis, adjusted for PSA density and age, PI-RADS score 4 or 5 (odds ratio (OR) 4.1, 95% CI 1.2-14.2, p=0.027) and clinical CAPRA score (OR 1.4, 95% CI 1.0-1.9, p=0.026) were significantly and independently associated with higher risk of adverse pathology. This study is limited by its retrospective nature. _x000D_

Conclusions

PI-RADS v2 score 4 or 5 on mpMRI is highly sensitive for the detection and prediction of adverse pathology. PI-RADS v2 may help improve the detection and staging of prostate cancer and allow for tailored intervention. _x000D_

Funding

none