SIU 2017: Advanced Risk Modeling for Prostate Cancer

Lisbon, Portugal (UroToday.com) Dr. Hadaschik followed Dr. Villers’ talk with a presentation on advanced risk modeling for prostate cancer. He began with some data regarding MRI.

Sensitivity and Specificity of mpMRI

  • PROMIS study – mpMRI and fusion biopsies detect >90% of significant prostate cancers (high sensitivity)
  • Specificity, however, especially for PIRADS 3 lesions, was only 60%
  • Potentially high inter-reader variability
  • Ultimately, MRI is very good at picking up large, aggressive tumors
Sensitivity and Specificity of PSA screening

  • PSA screening has high sensitivity, but very low specificity
  • MV risk models can reduce unnecessary biopsies by up to 30%
  • IE Rotterdam ERSPC risk calculators 3&4
In this presentation, Dr. Hadaschik wanted to assess the value of combining those risk calculators and mpMRI imaging to predict significant prostate cancers (ISUP > 2). Can we further reduce unnecessary biopsies?

Study:

  • All men underwent mpMRI
  • 24 core Transperineal systematic and 2-4 cores for targeted biopsies – median 27 cores
  • Retrospective study of 1159 patients
  • 670 biopsy naïve men
  • 489 men with previous biopsy
  • 732 (63%) had PCa detected
  • 489 (42%) had significant prostate cancer
Results:

  • On MV analysis looking at predictors of identifying significant PCa – MRI PIRADS 4-5 was by far the strongest predictor. Both in the biopsy naïve men and the prior biopsy men.
  • Adding MR to the pathway increases the ability to identify significant PCa
  • Generating a risk model for both groups
  • MRI was more important than the PSA
  • Risk model was better than the components alone in both groups
  • AUC 0.83 (biopsy naïve)
  • AUC 0.81 (prior biopsy)
  • However, its still not perfect!
  • Incorporating risk models and MRI help reduce the risk of unnecessary biopsy
Next, they are planning on external validation. However, the future is likely expanded risk models to include more tests to help improve the efficacy. 


Presented by: Boris Hadaschik

Written by: Thenappan Chandrasekar, MD, Clinical Fellow, University of Toronto, Twitter: @tchandra_uromd at the 37th Congress of Société Internationale d’Urologie - October 19-22, 2017- Lisbon, Portugal