Primary Noncontrast Magnetic Resonance Imaging for Prostate Cancer Screening: A Randomized Clinical Trial (PROSA)

Area of Science:

• Urology
• Radiology
• Oncology

Background:

• Prostate-specific antigen (PSA) screening for prostate cancer (PCa) has limitations in accuracy and leads to overdiagnosis.
• Current screening methods necessitate improvement for detecting clinically significant PCa (csPCa).

Purpose of the Study:

• To evaluate a contrast-free biparametric MRI (bpMRI)-first screening strategy for detecting csPCa.
• To assess secondary outcomes including overall PCa detection, benefit-harm metrics, and cost-effectiveness.

Main Methods:

• A single-center randomized controlled trial involving 816 asymptomatic men aged 49-69.
• Two arms: Arm A (bpMRI regardless of PSA), Arm B (bpMRI only if PSA ≥3 ng/ml or 2.5 ng/ml with family history).
• Targeted biopsy for men with Prostate Imaging Reporting and Data System score ≥3; csPCa defined as International Society of Urological Pathology grade group ≥2.

Main Results:

• Higher csPCa detection rates in the MRI-first arm (4.6%) compared to the standard arm (1.8%), with a relative risk of 2.6 (p=0.05).
• Improved benefit-harm metrics in the MRI-first strategy, including higher grade selectivity and biopsy avoidance.
• The MRI-first strategy demonstrated an incremental cost-effectiveness ratio of €2201.75 per csPCa case detected.

Conclusions:

• A contrast-free MRI-first pathway significantly enhances the detection of clinically significant prostate cancer.
• This strategy improves benefit-harm metrics and demonstrates favorable cost-effectiveness in prostate cancer screening.
• The findings support the implementation of MRI-first approaches in prostate cancer screening protocols.