Prostate Imaging Reporting and Data System (PI-RADS) and prostate cancer

Prostate Imaging Reporting and Data System (PI-RADS) assessment

PI-RADS version 2 (v2) uses a 5-point assessment scale indicating the likelihood that magnetic resonance imaging (mpMRI) findings correlate with the presence of clinically significant prostate cancer at a particular anatomic location:

• based on the current capabilities of mpMRI, clinically significant disease is defined as Gleason score >7 (including 3 + 4 with prominent but not predominant Gleason grade 4), and tumour volume >0.5 ml, and/or extraprostatic extension
• PI-RADS assessment categories derived from mpMRI examinations relate to likely histopathologic findings only and do not incorporate other patient or cancer characteristics, such as PSA or clinical cancer risk categories, and they do not directly inform the choice of treatments available if prostate cancer is diagnosed.

The PI-RADS v2 assessment categories are defined with the following scores:

• 1: Very low (clinically significant prostate cancer is highly unlikely to be present)
• 2: Low (clinically significant prostate cancer is unlikely to be present)
• 3: Intermediate (the presence of clinically prostate cancer disease is equivocal)
• 4: High (clinically significant prostate cancer is likely to be present)
• 5: Very high (clinically significant prostate canceris highly likely to be present)

Reference:

1. Barentsz JO et al. Synopsis of the PI-RADS v2 Guidelines for Multiparametric Prostate Magnetic Resonance Imaging and Recommendations for Use. Eur Urol. 2016 Jan;69(1):41-9.
2. Spektor M, Mathur M, Weinreb JC. Standards for MRI reporting-the evolution to PI-RADS v 2.0. Transl Androl Urol. 2017 Jun;6(3):355-367.