Please see the Editorial Comment by Daniel J. A. Margolis discussing this article.

This article reviews the clinical application of the Prostate Imaging for Recurrence Reporting (PI-RR) system. This system, released in 2021, represents international consensus-based guidelines for the acquisition, interpretation, and reporting of multiparametric MRI performed to detect locally recurrent prostate cancer after radiation therapy or radical prostatectomy. The system seeks to reduce variability by providing a standardized and structured reporting approach that classifies the overall level of suspicion for recurrence using a 5-point scale. The overall suspicion score is itself derived from 5-point scales for assessing DWI and dynamic-contrast enhancement imaging (DCE). Separate scales for both DWI and DCE are provided for evaluation after radiation therapy and after radical prostatectomy. These scales account for the relationship between detected abnormalities and the location of the primary tumor on pretreatment imaging. T2-weighted imaging is also assessed using a 5-point scale and is useful for anatomic imaging, but does not influence the overall score. Initial retrospective studies have shown promising results with respect to the reproducibility and accuracy of PI-RR in detecting locally recurrent tumor.