ESR Essentials: MRI-based T-staging in prostate cancer-practice recommendations by the European Society of Urogenital Radiology.

MRI-based T-staging in prostate cancer enables more precise and individualised treatment decisions compared with traditional clinical T-staging, yet inconsistent image acquisition, interpretation, and terminology limit reproducibility and clinical integration. This report recommends standardising MRI-based T-staging to strengthen its prognostic and therapeutic relevance. The prefix "mr" for MRI-based T-staging should be used, together with "extraprostatic extension" as the official radiologic term, replacing "extracapsular extension", to ensure consistency with pathology and the UICC TNM system. Within mrT3a disease, radiologists should differentiate "focal" from "established" extraprostatic extension, as established disease carries a higher recurrence risk and often requires more extensive surgical or radiotherapeutic management. Quality assurance programs, standardised acquisition protocols, and targeted education for radiologists and technologists are essential for improving interinstitutional consistency. Clinicians should incorporate proposed terminology and focal/established subclassification into structured reports and multidisciplinary discussions to refine risk stratification and guide nerve-sparing surgery or adjuvant therapy decisions. These coordinated measures will enhance the reproducibility and prognostic value of MRI-based T-staging, reduce overtreatment, and improve patient outcomes in contemporary prostate cancer management. KEY POINTS: The prefix "mr" should be added to T-staging for reporting and multidisciplinary team guidance, distinguishing it from clinical and pathological T-staging; extraprostatic extension should be explicitly defined as mrT3a. Staging assessment should be refined by subclassifying focal versus established extraprostatic extension to better guide risk stratification and treatment decisions. More reproducible and objective criteria of MRI-derived parameters should be adopted to reduce interpretation variability and to improve reader reproducibility.