Prostate imaging reporting and data system version 2 (PI-RADS v2): a pictorial review

Area of Science:

• Radiology
• Oncology
• Medical Imaging

Background:

• Prostate cancer diagnosis relies on accurate imaging interpretation.
• The Prostate Imaging Reporting and Data System (PI-RADS) provides standardized reporting for prostate MRI.
• PI-RADS version 2 (PI-RADS v2) is the latest expert consensus for multiparametric MRI (mpMRI).

Purpose of the Study:

• To outline the technical standards and reporting structure of PI-RADS v2.
• To explain the mpMRI sequences recommended by PI-RADS v2.
• To describe the PI-RADS v2 scoring system for assessing clinically significant prostate cancer.

Main Methods:

• PI-RADS v2 specifies minimum technical standards for MR image acquisition.
• Recommended mpMRI sequences include T1-weighted, T2-weighted (T2W), diffusion-weighted (DWI), and dynamic contrast-enhanced (DCE) imaging.
• PI-RADS v2 employs a dominant MR sequence based on lesion location (DWI for peripheral zone, T2W for transition zone).

Main Results:

• PI-RADS v2 provides a structured method for mpMRI reporting.
• The scoring system assesses the likelihood of clinically significant cancer (Gleason score ≥7, volume >0.5 cc, or extraprostatic extension).
• The dominant sequence concept differs from PI-RADS v1, focusing on specific sequences for different prostate zones.

Conclusions:

• PI-RADS v2 offers a standardized approach to mpMRI for prostate cancer.
• The system aids in differentiating clinically significant cancers from insignificant ones.
• Understanding the dominant sequence concept is crucial for accurate PI-RADS v2 interpretation.