Table 1. PIRADS scoring for (A) T2w imaging, (B) DWI and (C) DCE imaging, according to the 2015 version of the American College of Radiologists (58).
| Score | PZ or TZ |
|---|---|
| A: T2-weighted imaging | |
| 1 | PZ: uniform hyperintens signal intensity (normal); TZ: homogeneous intermediate signal intensity (normal) |
| 2 | PZ: linear or wedge-shaped hypointensity or diffuse mild hypointensity, usually indistinct margin;TZ: circumscribed hypointense or heterogeneous encapsulated nodules |
| 3 | PZ: heterogeneous signal intensity or non-circumscribed, rounded, moderate hypointensity Includes others that do not qualify as 2, 4 or 5;TZ: heterogeneous signal intensity with obscured margins. Includes others that do not qualify as 2, 4 or 5 |
| 4 | PZ: circumscribed, homogenous moderate hypointense focus/mass confined to prostate and <1.5 cm in greatest dimension;TZ: lenticular or non-circumscribed, homogeneous moderately hypointense, and <1.5 cm in greatest dimension |
| 5 | PZ: same as 4 but ≥1.5 cm in greatest dimension or definite extraprostatic extension/invasive behaviour;TZ: Same as 4 but ≥1.5 cm in greatest dimension or definite extraprostatic extension/invasive behaviour |
| B: Diffusion-weighted imaging | |
| 1 | No abnormality (i.e., normal) on ADC and high b value DWI |
| 2 | Indistinct hypointense on ADC |
| 3 | Focal mildly/moderately hypointense on ADC and isointense/mildly hyperintense on high b value DWI |
| 4 | Focal markedly hypointense on ADC and markedly hyperintense on high b value DWI; <1.5 cm in greatest dimension |
| 5 | Same as 4 but ≥1.5 cm in greatest dimension or definite extraprostatic extension (EPE)/invasive behaviour |
| C: Dynamic contrast enhanced imaging | |
| – | No early enhancement, or; diffuse enhancement not corresponding to a focal finding on T2 and/or DWI or; focal enhancement corresponding to a lesion demonstrating features of BPH on T2w |
| + | focal, and; earlier than or contemporaneously with enhancement of adjacent normal prostatic tissues, and; corresponds to suspicious finding on T2w and/or DWI |
PIRADS, Prostate Imaging Reporting and Data System; PZ, peripheral zone; TZ, transition zone; ADC, apparent diffusion coefficient; DWI, diffusion weighted imaging.