MRI-Assisted Guidance for Non-Essential Tissue Sampling

MRI-Assisted Guidance for Non-Essential Tissue Sampling (MAGNET): an Investigator-initiated, International, Multicentre, Prospective, Pairedcohort, Diagnostic Utility Study

The study aims to determine if a less painful and less invasive prostate biopsy approach is safe for certain men with a high risk of prostate cancer.

Currently, when a man has a suspicious MRI scan, standard medical guidelines recommend a "combined biopsy." This means the urologist performs a Targeted Biopsy (taking 3-5 tissue samples directly from the suspicious area seen on the MRI) followed immediately by a Systematic Biopsy (taking 12 additional samples blindly from the rest of the prostate). While this combined approach maximizes cancer detection, the 12 extra needles from the systematic biopsy increase the risk of bleeding, pain, and urinary infection.

Researchers believe that for men who already have a very high prostate-specific antigen (PSA) level and a highly suspicious MRI, the targeted biopsy alone might be enough to detect any dangerous cancer. In these high-risk men, the extra 12 systematic needles might offer little to no additional benefit ("diminishing returns").

In this study, 850 men will undergo the standard combined biopsy procedure. However, to test the researchers' theory with extreme precision, the tissue samples from the Targeted Biopsy and the Systematic Biopsy will be placed into completely separate, uniquely barcoded jars (the "One Core, One Jar" spatial mapping protocol). The pathologist will examine each tissue sample independently, without knowing which method was used to collect it.

By comparing the results within each patient, the study will determine exactly how many dangerous cancers were found exclusively by the systematic biopsy. If this number is clinically negligible (less than 5%) in men with high PSA levels, it will prove that the 12 extra needles are unnecessary for this specific group.

The ultimate goal of the trial is to safely "de-escalate" prostate cancer diagnostics-sparing high-risk men from the physical trauma, complications, and costs of unnecessary systematic sampling, while ensuring no dangerous cancers are missed.

Study Overview

• Status: Not yet recruiting
• Conditions: PSA Progression; PSA
• Intervention / Treatment: Procedure: Paired Prostate Biopsy Cohort (TB + SB)

• Study Type: Interventional
• Enrollment (Estimated): 850
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Shanghai East hospital ethics committee; Phone Number: 86-021-38804518; Email: siwei_bao@163.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

Age ≥ 45 years. Serum PSA level ≥ 4.0 ng/ml. High-risk MRI findings: Presence of at least one lesion with a PI-RADS score of 4 (Likely) or 5 (Highly Likely) according to v2.1 guidelines11.

Fitness for transperineal prostate biopsy under local or general anaesthesia. Competency to provide informed consent.

Exclusion Criteria:

History of prior prostate biopsy (to ensure baseline risk homogeneity). Prior treatment for prostate cancer or use of 5-alpha reductase inhibitors (5-ARIs) within 6 months.

Candidates who have explicitly opted for focal therapy prior to biopsy (where systematic mapping remains mandatory).

Contraindications to MRI (e.g., incompatible implants, severe renal impairment).

Active urinary tract infection or acute prostatitis.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Paired Prostate Biopsy Cohort (TB + SB)

Procedure: Paired Prostate Biopsy Cohort (TB + SB); All enrolled participants (PSA ≥ 4.0 ng/mL and PI-RADS 4-5 lesions) will undergo a standardized paired biopsy procedure during a single clinical session. Step 1: MRI-Targeted Biopsy (TB) of the index lesion(s). Step 2: A standard 12-core Systematic Biopsy (SB) covering the peripheral and transition zones. To allow for independent and unbiased pathological evaluation, biopsy cores will be strictly handled using a high-fidelity "One Core, One Jar" spatial mapping protocol. The diagnostic utility (incremental detection rate) of the systematic biopsy will be compared within-patient and further analyzed across two pre-specified risk strata (PSA 4-20 ng/mL vs. PSA > 20 ng/mL).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The primary endpoint is the Incremental Detection Rate (IDR) of clinically significant prostate cancer provided by systematic biopsy	Absolute Marker Framework: Stratified by serum PSA (> 20 ng/ml vs. 4-20 ng/ml).; Relative Marker Framework: Stratified by PSA Density (PSAD), utilizing a pre-specified threshold (e.g., ≥ 0.15 ng/ml² vs. < 0.15 ng/ml²). Both frameworks aim to validate a 'stopping rule' for systematic biopsy."	within 2 weeks after biopsy

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Rate of Treatment Management Change	The proportion of patients in whom the addition of Systematic Biopsy findings alters the recommended treatment plan compared to the plan based on Targeted Biopsy findings alone	within 2 weeks after biopsy
Pathological Upgrading Rate	The proportion of patients in whom Systematic Biopsy detects a higher ISUP Grade Group than that detected by Targeted Biopsy.	Within 2 weeks after biopsy
Diagnostic Accuracy Metrics	Sensitivity, Specificity, NPV, and PPV of the "Target-Only" strategy, using the "Combined Biopsy" result as the composite reference standard.	within 2 weeks after biopsy
Virtual Safety Analysis	A modelled analysis estimating the reduction in adverse events (e.g., haematuria, retention) if Systematic Biopsy had been omitted in the Experimental Stratum. This is calculated based on the "Number of Cores Saved" multiplied by per-core complication risk coefficients derived from trial safety data.	within 2 weeks after biopsy

Collaborators and Investigators

• Sponsor: Shanghai East Hospital

Study record dates

Study Major Dates

• Study Start (Estimated): April 5, 2026
• Primary Completion (Estimated): April 5, 2028
• Study Completion (Estimated): May 5, 2028

Study Registration Dates

• First Submitted: March 31, 2026
• First Submitted That Met QC Criteria: March 31, 2026
• First Posted (Actual): April 7, 2026

Study Record Updates

• Last Update Posted (Actual): April 7, 2026
• Last Update Submitted That Met QC Criteria: March 31, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: MRI; prostate biopsy; targeted biopsy; systematic biopsy
• Other Study ID Numbers: 2026044

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No