Prostate Imaging Standards for Screening Magnetic Resonance Imaging (PRISM)

Importance: Magnetic resonance imaging (MRI) is routinely used in prostate cancer diagnosis, but there is uncertainty about its optimal use in population-level screening. Objective: To provide consensus recommendations on the acquisition, interpretation, and reporting of prostate MRI for cancer screening. Evidence Review: A systematic review and meta-analysis of randomized clinical trials and prospective cohort studies evaluating MRI for prostate cancer screening was conducted for these international consensus recommendations. A search of PubMed, CENTRAL, Scopus, Web of Science, and ClinicalTrials.gov, citation searching, and consultation with experts was performed in September 2024. Studies performing upfront MRI for the purpose of prostate cancer screening were included. Findings: A total of 6 studies were identified and included 1919 participants, of whom 1426 underwent upfront screening MRI. Most studies used 3.0-T non-contrast-enhanced MRI. The pooled biopsy recommendation rate was 19.2% (95% CI, 11.7-26.7), with grade group (GG) 2 or higher prostate cancer detection of 6.0% (95% CI, 3.1-9.0) and GG1 cancer detection of 1.4% (95% CI, 0.7-2.2). The positive predictive value for GG2 or higher cancer was 36.3% (95% CI, 21.1-51.4). Findings informed a RAND/UCLA Appropriateness Method consensus exercise used to produce the Prostate Imaging Standards for Screening Magnetic Resonance Imaging (PRISM) recommendations. A total of 21 experts (8 urologists, 11 radiologists, and 2 pathologists from 6 countries) were included on the panel. Among 323 consensus statements, 235 (72.8%) reached agreement. If MRI is used in screening, it is recommended for men with an estimated life expectancy greater than 10 years and aged 50 to 70 years or from age 45 years in Black men. Screening MRI should be performed in men after a prostate-specific antigen (PSA) test, but there was no consensus on the optimal PSA threshold. Non-contrast-enhanced MRI with only T2-weighted and diffusion-weighted imaging was considered appropriate, with a maximum acceptable acquisition time of 15 minutes. The stage-gated (2-step) approach to reporting, where all MRI sequences are only revealed (second step) if a concordant focal lesion is identified on axial T2-weighted and high b-value diffusion imaging (first step), was recommended. Repeat screening should be risk stratified according to patient characteristics. Screening MRI should only be performed in accredited centers with radiologists meeting minimum reporting requirements and quality standards. Conclusions and Relevance: The PRISM consensus recommendations provide standardized expert guidance on the use of MRI in prostate cancer screening trials and future screening programs, including abbreviated non-contrast-enhanced MRI protocols, recommended screening intervals, stage-gated reporting, and quality assurance standards.