Clinical Scorecard: Evaluating the Effectiveness of Shortened Biparametric MRI for Prostate Cancer Detection: A Prospective Feasibility Investigation (ReIMAGINE Study)

At a Glance

Key Highlights

• Shortened bpMRI protocol (<10 min) omits contrast agents and ADC maps, reducing scan time and cost while maintaining diagnostic accuracy for csPCa.
• Screening MRI categorized as 'screen positive' or 'screen negative' with a high threshold for positivity to balance detection and false positives.
• Screen-positive men referred to secondary care for further mpMRI and biopsy as per NICE guidelines; screen-negative men exited study.

Guideline-Based Recommendations

Diagnosis

• Use PSA testing as initial screening but recognize its limited sensitivity and specificity.
• Employ shortened bpMRI as a feasible screening tool with high negative predictive value for csPCa.
• Define screen positivity by MRI findings and prostate-specific antigen density (PSAd ≥ 0.12 ng/mL2).

Management

• Refer screen-positive men to secondary care via two-week-wait suspected cancer pathway following NICE guidelines.
• Perform mpMRI and targeted transperineal biopsy in screen-positive men based on clinical decision-making.
• Use a composite reference standard including 2-year follow-up, biopsy, and mpMRI outcomes for diagnostic confirmation.

Monitoring & Follow-up

• Follow screen-positive men with electronic health record review for at least 2 years post-screening.
• Exclude screen-positive men not referred to secondary care from primary outcome analysis.
• Assume screen-negative men as reference standard negative for csPCa.

Risks

• Potential harms from PSA screening include under- and overdiagnosis leading to unnecessary investigations and treatments.
• False positives from MRI screening may lead to unnecessary biopsies and interventions.
• Avoid gadolinium-based contrast agents to reduce safety concerns.

Patient & Prescribing Data

Men aged 50–75 years without prior prostate cancer diagnosis undergoing population-based screening

Shortened bpMRI is a feasible, non-contrast screening modality with reduced scan time and cost, enabling targeted biopsy referral and potentially improving screening scalability.

Clinical Best Practices

• Utilize a two-sequence abbreviated bpMRI protocol (axial T2WI and high b-value DWI) without contrast or ADC maps for screening.
• Apply a high threshold for MRI screen positivity to optimize positive predictive value and reduce false positives.
• Calculate prostate-specific antigen density (PSAd) to complement MRI findings in determining screen positivity.
• Ensure blinded independent MRI reporting by experienced radiologists with adjudication for disagreements.
• Refer screen-positive patients promptly to secondary care following established cancer pathways.
• Use targeted transperineal biopsy guided by MRI findings for diagnostic confirmation.

References

• ReIMAGINE Prostate Cancer Screening study protocol and outcomes
• European Randomised study of Screening for Prostate Cancer (ERSPC)
• Prostate Imaging Reporting and Data System (PI-RADS) v2.1