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

This publication is a consensus‑style recommendations paper focused on standardising MRI-based T-staging in prostate cancer to improve prognostic relevance and treatment planning.

Key points:

• Use of “mr” prefix:
  • MRI-derived T-stage should be explicitly labeled with the prefix “mr” (e.g., mrT2, mrT3a) to distinguish it from clinical (digital rectal exam–based) and pathological T-staging.
  • This is intended to avoid confusion in multidisciplinary discussions and documentation.
• Terminology alignment with pathology/TNM:
  • The term “extraprostatic extension” (EPE) is recommended as the official radiologic term, replacing “extracapsular extension,” to align with pathology reports and the UICC TNM system.
  • EPE on MRI corresponds to mrT3a disease.
• Subclassification of mrT3a (EPE):
  • Radiologists should distinguish:
    • “Focal” EPE – limited, small-volume extension beyond the prostate.
    • “Established” EPE – more extensive, definite extension.
  • Established EPE is associated with a higher recurrence risk and typically warrants more aggressive or less nerve‑sparing surgery and/or intensified radiotherapy strategies.
• Clinical implications:
  • Incorporating the mr-prefix, EPE terminology, and focal/established subclassification into structured MRI reports and tumor board discussions can:
    • Refine risk stratification beyond traditional clinical T-stage.
    • Better guide nerve-sparing decisions, margin risk assessment, and use of adjuvant or escalated therapies.
    • Help reduce both overtreatment and undertreatment.
• Standardisation and quality assurance:
  • The authors emphasize:
    • Standardised acquisition protocols for prostate MRI.
    • Objective, reproducible criteria for MRI signs of EPE (e.g., measurable and clearly defined features) to minimize inter-reader variability.
    • Quality assurance programs and targeted training for radiologists and technologists to improve consistency across institutions.

Overall, the paper argues that harmonised MRI-based T-staging nomenclature and criteria—particularly the mr-prefix, use of “extraprostatic extension,” and focal vs established EPE subclassification—will make MRI staging more reproducible, clinically actionable, and better integrated into contemporary prostate cancer management.