Active surveillance (AS) is an increasingly adopted strategy for men with low-risk or selected favorable intermediate-risk prostate cancer and is aimed at avoiding overtreatment while maintaining close monitoring. MRI has been integrated into AS protocols to help improve risk stratification, identify clinically significant disease, and guide targeted biopsies. During AS, MRI is integral to assessing the stability or interval progression of imaging findings. It can also allow identification of new lesions, potentially prompting a reassessment of treatment strategies. The PRECISE (Prostate Cancer Radiologic Estimation of Change in Sequential Evaluation) criteria, recently updated to version 2, offer a structured reporting system for serial MRI evaluations during AS. PRECISE version 2 introduced simplified guidelines for assessing longitudinal changes in MRI examination of the prostate, which focus on lesion size, appearance, and the development of new lesions. It involves a 1-5 Likert scoring system to categorize the likelihood of changes at MRI over time to standardize communication between radiologists and clinicians. The authors provide an overview of the rationale and criteria for patient selection for an AS protocol, review the foundations and evolution of the PRECISE system, and demonstrate how to integrate clinical and MRI findings, including a series of practical cases. ©RSNA, 2026 Supplemental material is available for this article.
Ogata et al. (2026) studied this question.