PRECISE Assistant | Prostate MRI Toolkit

1. Minimum scan context

PRECISE is based on change over time.

Use this for patients on active surveillance. Compare the current MRI with both the baseline MRI and the most recent prior MRI when available, and state which comparison drives the score. All about PRECISE scoring for active surveillance MRI.

Comparison driving score Image quality

2. Select score-driving MRI change

Not selected

Progression details

Optional

There is no single universally accepted quantitative threshold for significant size increase. Use lesion size, conspicuity, ADC/DWI change, and clinical context.

New PI-RADS/Likert ≥3 lesion on current MRI. Interval increase in lesion size. Interval increase in lesion conspicuity / more convincing restricted diffusion. Definite extraprostatic extension or progression to ≥T3a.

Optional report details

Used only in the description.

Index lesion / location Prior/current size

PSA / density / kinetics Biopsy context

Optional note for description

Overall assessment

PRECISE

Select MRI change

PRECISE summarizes radiologic change on serial MRI during active surveillance.

Decision logic

Score	Meaning
1–2	Radiologic regression
3-V / 3-NonV	Stable visible or stable non-visible disease
4–5	Radiologic progression
X	Insufficient image quality

Suggested assessment description

Choose the MRI change pattern to generate a suggested assessment description.

All about PRECISE scoring for active surveillance MRI

A short, practical primer explaining how PRECISE tracks radiologic change over time and how it differs from PI-RADS.

Read the article

PRECISE v2: Serial MRI Scoring for Prostate Cancer Active Surveillance

PRECISE (PRostate Evaluation for Clinically Important disease: Standardising Evaluation) is a scoring system for reporting radiologic change on serial prostate MRI in men on active surveillance. It was developed by an international group of prostate MRI experts and is endorsed by major societies including the ESUR. The system is designed to complement pathologic and PSA-based surveillance triggers by providing a standardized vocabulary for MRI change over time.

When PRECISE is applied

PRECISE is applied when reading a surveillance MRI for a man with a known low- or favorable-intermediate-risk prostate cancer who is being managed without immediate treatment. The scoring requires access to prior MRI examinations, ideally the original diagnostic (baseline) MRI and the most recent prior surveillance MRI. Both comparisons should be stated in the report, with the comparison that drives the score identified explicitly.

Score categories and key thresholds

PRECISE scores run from 1 to 5. Score 1 indicates that a previously present lesion has resolved. Score 2 means the MRI findings are stable with no increase in suspicion. Score 3 is the most nuanced category: it is subdivided into 3-V (volume increase only, no change in PI-RADS score) and 3-NonV (stable volume but change in morphology or T2/DWI signal not amounting to a full PI-RADS upgrade). Score 4 indicates new or increasing MRI suspicion, while Score 5 indicates progressive change strongly suspicious for tumor progression. PRECISE-X is assigned when technically adequate comparison is not possible.

Management thresholds vary by protocol, but PRECISE 4 or 5 generally triggers rebiopsy in most active surveillance programs. PRECISE 3-V lesions are often managed with continued surveillance and shorter follow-up intervals.

PRECISE: Frequently Asked Questions

What is the difference between PRECISE 3-V and 3-NonV?

PRECISE 3 is subdivided based on the nature of the change. PRECISE 3-V indicates that the lesion has increased in volume compared to prior imaging, but the PI-RADS category has not changed; the lesion is bigger but not more suspicious in character. PRECISE 3-NonV indicates a qualitative change in lesion appearance (such as a shift in T2 signal, ADC values, or morphology) without a volume increase that meets the threshold for PRECISE 4. Both subcategories sit in an intermediate zone where management is guided by overall clinical context.

What does PRECISE-X mean?

PRECISE-X is assigned when a meaningful comparison to prior MRI is not possible due to technical factors (for example, when the prior MRI is not available, was performed at significantly different field strength or protocol, or when image quality differences preclude reliable comparison). It is not a score indicating progression or stability; it documents that serial assessment was technically limited. In these cases, management should be based on the absolute findings of the current study and clinical risk assessment.

Which prior MRI should drive the PRECISE score?

PRECISE v2 recommends comparing the current MRI to both the baseline MRI (the diagnostic study that established the diagnosis) and the most recent prior surveillance MRI. When these two comparisons yield different scores, the report should state which comparison drives the assigned PRECISE score and why. In practice, comparing to baseline best captures cumulative change over the full surveillance period, while comparing to the most recent prior MRI highlights short-interval change.

At what PRECISE score does most guidance recommend rebiopsy?

Most active surveillance protocols use PRECISE 4 (new or increasing MRI suspicion) or PRECISE 5 (progressive change strongly suspicious for progression) as triggers for repeat targeted biopsy. PRECISE 3-V and 3-NonV occupy an intermediate zone where the decision depends on the overall clinical picture, including PSA kinetics, prior biopsy grade, and patient preferences. Local active surveillance protocols may vary, and the PRECISE score should always be interpreted alongside these other parameters.