Diagnostic pathways based on PSA, digital rectal examination (DRE), and systematic biopsy (SB) may miss clinically significant prostate cancer (csPCa) and lead to overdiagnosis of indolent disease. Multiparametric MRI (mpMRI) and MRI-targeted biopsy (TB) improve detection of csPCa; however, the additional diagnostic value of routine SB in biopsy-naïve men with suspicious MRI findings remains controversial.
PRIMA is a randomized, prospective, multicenter non-inferiority diagnostic accuracy trial in eight German hospitals. Biopsy-naïve men aged 50-75 years with PSA ≥ 3 ng/ml and/or suspicious DRE undergo mpMRI (PI-RADS v2.1, PI-QUAL v2). Men with PI-RADS 4-5 or PI-RADS 3 with PSA density > 0.15 are randomized 1:1 to TB only (Arm A) or TB + SB (Arm B). Persistent PI-RADS 4-5 lesions with negative biopsy undergo MRI in-bore biopsy.
Co-primary endpoints are csPCa (ISUP ≥ 2) detection and detection of clinically insignificant cancer (ISUP 1). Secondary endpoints include patient-reported outcomes (EORTC-QLQ-C30, EPIC-26, VAS), biopsy-related complications, biopsy approach, MRI in-bore yield, AI/radiomics validation and follow-up cancer incidence.
One thousand nine hundred eight men were allocated to achieve 1590 analyzable patients (> 80% power; non-inferiority margin δ = 13%).
PRIMA will provide high-level evidence whether systematic biopsy can be safely omitted in MRI-positive biopsy-naïve men, potentially reducing diagnostic morbidity and overtreatment.
ClinicalTrials.gov NCT04993508. Registered on 2 December 2022.
Trials. 2026 Apr 25*** epublish ***
Rouvier Al-Monajjed, Peter Albers, Matthias Boschheidgen, Jan Philipp Radtke, Johanna Droop, Axel Benner, Boris Hadaschik, Gerald Antoch, Lars Schimmöller, PRIMA Study Group
Department of Urology, University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany. ., Department of Urology, University Hospital Düsseldorf, Heinrich-Heine-University, Düsseldorf, Germany., Department of Diagnostic and Interventional Radiology, University Hospital Düsseldorf, Düsseldorf, Germany., Division of Biostatistics (C060), German Cancer Research Center, Heidelberg, Germany., Department of Urology, University Hospital Essen, University of Duisburg-Essen, Essen, Germany.