Accuracy and Interobserver Agreement of the Correlation Between Prostate Imaging Reporting and Data System Version 2.1 and International Society of Urological Pathology Scores

Introduction: This research aims to evaluate accuracy and interobserver agreement on the correlation between the Prostate Imaging Reporting and Data System version 2.1 (PI-RADS v2.1) and the International Society of Urological Pathology (ISUP) scores. Methods: We examined patients who underwent prostate multiparametric magnetic resonance imaging (MpMRI) prior to transrectal ultrasound-guided cognitive fusion biopsy between April and December 2019. MpMRI examinations were evaluated by two radiologists according to PI-RADS v2.1. Interobserver agreement was recorded and the final PI-RADS category was decided by consensus. The correlation of cognitive fusion biopsy results with PI-RADS v2.1 score was evaluated. Lesions with Gleason score & GE;7 were considered to be clinically significant prostate cancer.Results: A total of 84 patients with 106 lesions were included in the study. The rates of prostate cancer in the PI -RADS groups 1, 2, 3, 4, and 5 were 0%, 0%, 22.2%, 56%, and 94.45%, respectively. There was a positive correlation with an area under the curve value of 0.814 between the PI-RADS v2.1 and the ISUP score. Using PI-RADS & GE;3 as the cut-off value in the peripheral zone (PZ) and the whole gland, the negative predictive value for malignancy was 100%. For PI-RADS & GE;4, it was 76.47% for PZ and 80.65% for the whole gland. Without applying cut-off values, the interobserver agreement for PI-RADS score was & kappa; = 0.562.Conclusion: Our data support the notion that PI-RADS v2.1 facilitates the evaluation of MpMRI and improves interobserver agreement.