Publications

Abstract

INTRODUCTION: To assess the accuracy of multiparametric magnetic resonance imaging (mpMRI) for significant PC detection before diagnostic biopsy in men with abnormal PSA/DRE. MATERIAL AND METHODS: 388 men underwent mpMRI including T2-weighted, diffusion-weighted & dynamic contrast-enhanced imaging prior to biopsy. Two radiologists used PIRADS reporting system to allocate a score of 1-5 for suspicion of significant PC (Gleason 7 with >5% grade 4). PIRADS score 3-5 was considered positive. Transperineal template-guided mapping biopsy of 18-regions (median 30 cores) were performed, with additional manually directed cores from MRI-positive regions. The anatomical location, size, and grade of individual cancer areas in the 18-biopsy regions, as primary outcome, and in prostatectomy specimens (n=117), as secondary outcome, were correlated to the MRI-positive regions. RESULTS: Of the 388 men that were enrolled, 344 were analyzed. mpMRI was positive in 77.0% of patients, 62.5% had PC and 41.6% had significant PC. Detection of significant PC by mpMRI had sensitivity of 96%, specificity of 36%, NPV and PPV were 92% and 52%. Adding PIRADS to the multivariate model including PSA, DRE, prostate volume and age improved the AUC from 0.776 to 0.879, p<0.001. Anatomical concordance analysis showed a low mismatch between the MRI-positive regions and biopsy-positive regions (n=4(2.9%)), and the significant PC area in RP specimen (n=3(3.3%)). CONCLUSIONS: In men with abnormal PSA/DRE, mpMRI detected significant PC with an excellent NPV and moderate PPV. The use of mpMRI for diagnosing significant PC may result in a substantial number of unnecessary biopsies while missing minimum number of significant PC.