Risk-adapted MRI Protocols for the Detection of Clinically Significant Prostate Cancer

Purpose: To compare the diagnostic performance and clinical utility of three MRI protocols for detecting clinically significant prostate cancer (csPCa) according to prebiopsy risk. Materials and Methods: This retrospective study included 390 male patients who underwent prostate multiparametric MRI (mpMRI) between January 2019 and April 2024 for suspected csPCa, followed by biopsy. Patients were stratified by Rotterdam Prostate Cancer Risk Calculator score into low-risk (<4%), intermediate-risk (4%-9%), and high-risk (≥10%) groups. Three datasets were generated from each examination: mpMRI (T2-weighted imaging, diffusion-weighted imaging [DWI], and dynamic contrast-enhanced imaging), unenhanced MRI (multiplanar T2-weighted imaging and DWI), and short MRI (axial T2-weighted imaging and DWI). Overall, 1170 datasets were randomly assigned to 10 expert radiologists (117 examinations each). Diagnostic performance for grade group 2 or greater cancer and clinical utility metrics were compared across risk groups. Results: Among the 390 patients (median age, 66 years [IQR, 61-71 years]), csPCa prevalence was 34.4% (134 of 390). In low-risk patients, short MRI demonstrated the highest sensitivity (95% [21 of 22]), with no significant differences among protocols (all P ≥ .21) and greatest potential for safe biopsy avoidance (84 biopsies avoided per missed csPCa). In intermediate-risk patients, mpMRI showed higher sensitivity (83% vs 72% for unenhanced MRI and 62% for short MRI; P = .012 for mpMRI vs short MRI) and higher biopsy efficiency (1.11 vs 0.85 for mpMRI vs unenhanced MRI). In high-risk patients, protocol-related differences were minimal (all P ≥ .12). Conclusion: mpMRI was associated with improved sensitivity and biopsy efficiency in intermediate-risk patients, whereas protocol differences were limited in low- and high-risk groups; these findings support risk-adapted selection of MRI protocols. Keywords: MR-Dynamic Contrast-enhanced, MR Imaging, Urinary, Prostate, Neoplasms-Primary, Efficacy Studies, Prostatic Neoplasms, MRI, Contrast Medium, Biopsy, Risk Assessment Supplemental material is available for this article. © RSNA, 2026.