PI-RADS: Meaning in a Radiology Report

Also written as: Prostate Imaging Reporting and Data System, PIRADS, PI-RADS v2.1

PI-RADS is a 1 to 5 score on prostate MRI for how likely an area is to be clinically significant prostate cancer, from very low to very high.

What it means

PI-RADS stands for Prostate Imaging Reporting and Data System. It estimates how likely an area on a prostate MRI is to be clinically significant cancer, meaning a cancer that may need treatment rather than just monitoring. The radiologist scores how the area looks on several MRI sequences, especially diffusion images, which highlight tightly packed cells. Each suspicious area gets its own score.

When it matters

A score of 1 means very low likelihood, 2 low, 3 intermediate, 4 high and 5 very high. A 4 or 5 usually leads to a discussion about a targeted biopsy. For a 3, doctors often weigh other factors, such as PSA density (PSA relative to prostate size), before deciding. A 1 or 2 often means a biopsy may not be needed, depending on PSA and other risk factors. The score is a likelihood, not a diagnosis.

Questions to ask your doctor

How many areas were scored, and where are they in the prostate?
Would a targeted biopsy be recommended for my score?
How does my PSA density affect what happens next?