Noninvasive Urine Test Predicts Grade Group Upgrading in Patients on Active Surveillance for Prostate Cancer:...

Area of Science:

• Urology
• Oncology
• Biomarker Development

Background:

• Active surveillance (AS) for prostate cancer requires regular monitoring, often involving biopsies.
• Current methods like multiparametric magnetic resonance imaging (mpMRI) have limitations in guiding biopsy decisions.
• There is a need for non-invasive tests to optimize AS management.

Purpose of the Study:

• To develop and validate a non-DRE urine test (MPS2-AS) for predicting Grade Group (GG) upgrading in patients on AS.
• To compare the diagnostic performance and clinical utility of MPS2-AS against mpMRI for informing biopsy necessity.
• To assess the potential of MPS2-AS to reduce unnecessary biopsies.

Main Methods:

• Biomarker models (MPS2-AS) were derived to predict GG≥3 and GG≥2 upgrading.
• External validation was performed across 11 clinical practices.
• Urine samples were collected prospectively from patients undergoing systematic and targeted biopsies.
• Diagnostic performance was compared to pre-biopsy mpMRI (PI-RADS scoring).

Main Results:

• The validation cohort included 330 patients with GG1 cancer on AS.
• MPS2-AS demonstrated higher AUC than mpMRI for predicting GG≥3 (0.82 vs. 0.73) and GG≥2 (0.74 vs. 0.64) upgrading.
• MPS2-AS could have avoided 64% of unnecessary biopsies while missing only 3.2% of GG≥3 upgrades.
• mpMRI (PI-RADS≥3) missed 18% of GG≥3 upgrades and avoided fewer biopsies (50%).
• MPS2-AS performance was consistent across subgroups.

Conclusions:

• Urinary MPS2-AS provides accurate and actionable risk stratification for GG upgrading in prostate cancer AS.
• MPS2-AS significantly outperforms mpMRI in predicting clinically significant cancer progression.
• Non-invasive monitoring with MPS2-AS may reduce the need for scheduled biopsies and serial mpMRI in AS.
• This urine test offers a promising tool for personalized management of men on active surveillance.