Multivariable stratification of PI-RADS version 2.1 categories for the risk of false-positive target biopsy: Impact

Rossano Girometti1, Gianluca Giannarini2, Maria De Martino3

  • 1Institute of Radiology, Department of Medicine (DAME), University of Udine, University Hospital S. Maria della Misericordia - Azienda Sanitaria-Universitaria Friuli Centrale (ASU FC), p.le S. Maria ella Misericordia, 15, 33100 Udine, Italy.

PubMed
Abstract

Insights

Identifying factors for false positive prostate cancer biopsies is crucial. A multivariable model using age, PSA density, and MRI findings improves biopsy targeting accuracy.

Area of Science:

  • Radiology
  • Urology
  • Oncology

Background:

  • Multiparametric magnetic resonance imaging (mpMRI) is vital for detecting clinically significant prostate cancer (csPCa).
  • Prostate Imaging Reporting and Data System version 2.1 (PI-RADSv2.1) categorizes lesions, guiding biopsy decisions.
  • False positive target biopsies (FP-TB) can lead to unnecessary procedures and patient anxiety.

Purpose of the Study:

  • To identify clinical and mpMRI factors that predict FP-TB in PI-RADSv2.1 ≥ 3 findings.
  • To develop a model for improving the accuracy of prostate cancer diagnosis and reducing unnecessary biopsies.

Main Methods:

  • Retrospective analysis of 221 men undergoing mpMRI and transperineal biopsy (systematic and targeted).
  • Development and internal validation of a multivariable model to predict FP-TB, defined as absence of csPCa (ISUP ≥ 2).
  • Analysis included age, prostate-specific antigen density (PSAD), PI-RADSv2.1 category, and lesion multifocality.

Main Results:

  • Younger age (<65 years), lower PSAD (<0.15 ng/mL/mL), and PI-RADS 4/5 categories were associated with higher FP-TB risk.
  • Multifocality was associated with a lower risk of FP-TB.
  • The multivariable model achieved an area under the curve (AUC) of 0.815 for predicting FP-TB.

Conclusions:

  • Adjusting PI-RADSv2.1 categories with a multivariable risk model is more effective for triggering target biopsies than unadjusted PI-RADS or PSAD adjustment alone.
  • This approach can potentially improve the accuracy of csPCa detection and reduce false positive biopsies.