Magnetic Resonance Imaging-Based Prostate-Specific Antigen Density for Prediction of Gleason Score Upgrade in Patients With Low-Risk Prostate Cancer on Initial Biopsy

Abstract

Objective: The aim of this study was to assess the utility of prostate-specific antigen density (PSAD) calculated using magnetic resonance imaging for predicting Gleason score (GS) upgrade in patients with low-risk prostate cancer on biopsy. Methods: Seventy-three patients were divided into 2 groups according to the concordance between biopsy and prostatectomy GS: group 1 (6/6) and group 2 (6/>= 7). Magnetic resonance imaging-based PSAD, prostate volume, prostate-specific antigen (PSA), and age were compared between the 2 groups. Logistic regression and receiver operating characteristic curve analysis were performed. Results: Gleason score was upgraded in 40 patients. Patients in group 2 had significantly higher PSAD and PSAvalues and smaller prostate volume than did those in group 1. Prostate-specific antigen density of 0.26 ng/mL per cm(3) or higher, PSA of 7.63 ng/mL or higher, and prostate volume of 25.1 cm(3) or less were related to GS upgrade, with area-underthe- curve values of 0.765, 0.721, and 0.639, respectively. Conclusions: Magnetic resonance imaging-based PSAD could help in predicting postoperative GS upgrade in patients with low-risk prostate cancer.