Prostate Imaging for Recurrence Reporting: User Guide

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• The Prostate Imaging Reporting and Data System (PI-RADS) standardizes prostate cancer imaging before treatment.
• Post-treatment assessment for recurrent prostate cancer using MRI requires different interpretation criteria than pre-treatment imaging.
• Standardization is needed for reliable detection and reporting of prostate cancer recurrence after radical prostatectomy (RP) or radiation therapy (RT).

Purpose of the Study:

• To introduce and explain the Prostate Imaging for Recurrence Reporting (PI-RR) system.
• To provide guidelines for the performance and interpretation of pelvic MRI in patients with suspected recurrent prostate cancer.
• To standardize the reporting of MRI findings indicative of prostate cancer recurrence.

Main Methods:

• The PI-RR system adapts principles from PI-RADS but emphasizes different imaging sequences and findings for recurrence detection.
• Key MRI findings for recurrence include focal early enhancement on dynamic contrast enhancement (DCE) images and diffusion restriction.
• The system utilizes a structured scoring approach based on established knowledge of recurrent prostate cancer MRI features.

Main Results:

• PI-RR provides a systematic framework for interpreting post-treatment prostate MRI.
• The system codifies scoring elements for T2-weighted, diffusion-weighted, and DCE imaging relevant to recurrence after RP and RT.
• Illustrative cases demonstrate the application of PI-RR in clinical practice.

Conclusions:

• The PI-RR system offers a standardized approach to reporting suspected prostate cancer recurrence on MRI.
• It aims to improve consistency and accuracy in the interpretation of post-treatment pelvic MRI.
• PI-RR serves as a comprehensive reference for radiologists of all experience levels.