| PI-RADS v.1[9] | PI-RADS v2[10] |
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Published by | ESUR (PI-RADS v1) | ACR/AdMeTech Foundation/ESUR (PI-RADS v2) |
Stratification of localized prostate cancer according the likelihood of tumor spread and recurrence | Low-risk: PSA <10 ng/mL, and biopsy Gleason score ≤6, and clinical stage T1–T2a
Intermediate-risk: PSA 10–20 ng/mL, or biopsy Gleason score 7, or clinical stage T2b or T2c High-risk: PSA >20 ng/mL, or Gleason score 8–10, or clinical stage >T2c | Focused on the detection and exclusion of clinically significant prostate cancer |
Timing of imaging | Not mentioned | > 6 weeks after biopsy |
Investigating men post-therapy with PSA rise | when curative aggressive treatment (e.g. salvage ra- diotherapy) is considered, in addition to T2WI, DCE-MRI and DWI should always be performed using the “detection protocol | Not applicable |
Definition of clinically significant cancer | Not defined | Gleason Grade 4 and above, and/or volume > 0.5cc |
DWI | 5 mm at 1.5 T, 4 mm at 3 T; in-plane resolution: 1.5 mm × 1.5 mm to 2.0 mm × 2.0 mm at 1.5 T and 1.0 mm × 1.0 mm to 1.5 mm × 1.5 mm at 3 T. ADC map should be calculated. At least 3 b-values should be acquired in three orthogonal directions and adapted to quality of SNR: 0, 100 and 800–1000 s/mm2. For calculation of ADC, the highest b-value that should be used is 1000 s/mm2. | Free breathing spin echo EPI sequence combined with spectral fat saturation is recommended. oTE:≤90msec;TR:>3000msec o Slice thickness: ≤4mm, no gap. Locations should match or be similar to those used for T2W and DCE o FOV: 16‐22 cm o In plane dimension: ≤ 2.5mm phase and frequency. |
DCE | 4 mm at 1.5 T and 3 T; in plane resolution: 1.0×1.0 mm at 1.5 T and 0.7×0.7 mm at 3 T. Quantitative or semi-quantitative DCE-MRI analysis does not have to be performed. Maximum temporal resolution should be 15 s following single dose of contrast agent with an injection rate of 3 mL/s. For DCE-MRI, imaging acquisition should be continued for 5 min to detect washout. Unenhanced T1WI images from this sequence can be used to detect post-biopsy haematomas. | DCE is generally carried out for several minutes to assess the enhancement characteristics. In order to detect early enhancing lesions in comparison to background prostatic tissue, temporal resolution should be <10 seconds and preferably <7 seconds per acquisition in order to depict focal early enhancement. Fat suppression and/or subtractions is recommended. Although either a 2D or 3D T1 gradient echo (GRE) sequence may be used, 3D is preferred. o TR/TE: <100msec/ <5msec o Slice thickness: 3 mm, no gap. Locations should be the same as those used for DWI and DCE o FOV: encompass the entire prostate gland and seminal vesicles o In plane dimension: ≤2 mm × ≤2 mm o Temporal resolution: ≤15 sec (<7 sec is preferred) o Total observation rate: >2min o Dose: 0.1 mmol/kg standard GBCA or equivalent high relaxivity GBCA o Injection rate: 2–3 cc/sec starting with continuous image data acquisition (should be the same for all exams) |
T2WI for the peripheral zone (PZ) | - Uniform high signal intensity (SI)
- Linear, wedge shaped, or geographic areas of lower SI, usually not well demarcated
- Intermediate appearances not in categories 1/2 or 4/5
- Discrete, homogeneous low signal focus/mass confined to the prostate
- Discrete, homogeneous low signal intensity focus with extracapsular extension/invasive behaviour or mass effect on the capsule (bulging), or broad (>1.5 cm) contact with the surface.
| - Uniform hyperintense signal intensity (normal)
- Linear or wedge-shaped hypointensity or diffuse mild hypointensity, usually indistinct margin
- Heterogeneous signal intensity or non-circumscribed, rounded, moderate hypointensity Includes others that do not qualify as 2, 4, or 5
- Circumscribed, homogenous moderate hypointense focus/mass confined to prostate and <1.5 cm in greatest dimension
- Same as 4 but ≥1.5 cm in greatest dimension or definite extraprostatic extension/invasive behavior
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T2WI for the transition zone (TZ) | - Heterogeneous TZ adenoma with welldefined margins: “organised chaos”
- Areas of more homogeneous low SI, however well marginated, originating from the TZ/BPH
- Intermediate appearances not in categories 1/2 or 4/5
- Areas of more homogeneous low SI, ill defined: “erased charcoal sign”
- Same as 4, but involving the anterior fibromuscular stroma or the anterior horn of the PZ, usually lenticular or waterdrop shaped.
| - Homogeneous intermediate signal intensity (normal)
- Circumscribed hypointense or heterogeneous encapsulated nodule(s) (BPH)
- Heterogeneous signal intensity with obscured margins Includes others that do not qualify as 2, 4, or 5
- Lenticlular or non-circumscribed, homogeneous, moderately hypointense, and <1.5 cm in greatest dimension
- Same as 4 but ≥1.5 cm in greatest dimension or definite extraprostatic extension/invasive behavior
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Scoring of extraprostatic disease | Extracapsular extension | Abutment: | 1 | Irregularity: | 3 | Neurovascular bundle thickening: | 4 | Bulge, loss of capsule: | 4 | Seminal vesicles | Expansion: | 1 | Low T2 signal: | 2 | Filling in of angle: | 3 | Enhancement and impeded diffusion: | 4 | Distal sphincter | Adjacent tumor: | 3 | Effacement of low signal sphincter muscle: | 3 | Abnormal enhancement extending into sphincter: | 4 | Bladder neck | Adjacent tumor: | 2 | Loss of low T2 signal in bladder muscle: | 3 | Abnormal enhancement extending into bladder neck: | 4 |
| Extraprostatic extension/ invasive behavior as PI-RADS 5 assessment independent of lesion localization in peripheral or transition zone on T2w or DWI |