PI-RADS v2.1 calculator
The dominant sequence depends on the zone: DWI in the peripheral zone, T2W in the transition zone. Getting that backwards is the commonest PI-RADS error, so the tool asks for the zone first.
The rule that catches people out. The dominant sequence depends on the zone. In the PERIPHERAL zone DWI is primary and DCE only breaks a tie at DWI 3. In the TRANSITION zone T2W is primary and DWI only breaks a tie at T2 3. Scoring a transition-zone lesion off DWI is the single most common PI-RADS error.
Assessment categories
| Category | Risk | Meaning |
|---|---|---|
| PI-RADS 1 | Very low | Clinically significant cancer is highly unlikely. |
| PI-RADS 2 | Low | Clinically significant cancer is unlikely. |
| PI-RADS 3 | Intermediate | The presence of clinically significant cancer is equivocal. |
| PI-RADS 4 | High | Clinically significant cancer is likely. |
| PI-RADS 5 | Very high | Clinically significant cancer is highly likely. |
Peripheral zone — DWI is primary
| DWI | DCE | PI-RADS |
|---|---|---|
| 1 | any | 1 |
| 2 | any | 2 |
| 3 | negative | 3 |
| 3 | positive | 4 |
| 4 | any | 4 |
| 5 | any | 5 |
Transition zone — T2W is primary
| T2W | DWI | PI-RADS |
|---|---|---|
| 1 | any | 1 |
| 2 | any | 2 |
| 3 | ≤4 | 3 |
| 3 | 5 | 4 |
| 4 | any | 4 |
| 5 | any | 5 |
DCE does not contribute in the transition zone under v2.1.
Related
Source. Turkbey B, et al. Eur Urol 2019;76(3):340-351. View on PubMed
This is a reference implementation of a published guideline, for use by qualified clinicians. It does not account for patient-specific factors and is not a substitute for clinical judgment or a formal radiology consultation. See our full disclaimer.