PROMIS Trial

Prostate MR Imaging Study: Evaluating the effectiveness of mpMRI in detecting prostate cancer with the aim of using mpMRI as a triage test to reduce unnecessary biopsies.

Summary

The PROMIS Trial (Prostate MR Imaging Study) was a pivotal clinical study comparing the effectiveness of multiparametric MRI (mpMRI) with transrectal ultrasound-guided (TRUS) biopsy in detecting clinically significant prostate cancer.

Objective

To evaluate whether using mpMRI as a preliminary test could improve the detection of clinically significant prostate cancer and reduce unnecessary biopsies.


Study Setup

  • Conducted in the UK at multiple centres.
  • Included 740 men who were suspected of having prostate cancer due to high PSA levels or abnormal physical exams.


    • Procedure

    All men had three tests:

    • mpMRI.
    • TRUS biopsy.
    • Template prostate mapping (TPM) biopsy, the standard, used as a comparison.


    Clinically Significant Cancer Definition

    Cancer with a Gleason score of at least 3+4 or a cancer core length of 4mm or more.


    mpMRI Accuracy

    • Detected 93% of clinically significant cancers (high sensitivity).
    • Specificity: 41%.
    • mpMRI identified far more (93%) significant cancers compared to TRUS biopsy (48%).

    Biopsy Reduction

    • Using mpMRI as a triage test could avoid unnecessary biopsies in 27% of men.
    • mpMRI reduced overdiagnosis of insignificant cancers (detecting fewer low-risk cases).

    Comparison to TRUS

    • TRUS biopsy missed 52% of clinically significant cancers.

      mpMRI outperformed TRUS biopsy in sensitivity but was less specific, meaning it sometimes flagged low-risk cases.


    Conclusion and Impact

    The PROMIS trial showed that mpMRI as a triage test reduces unnecessary biopsies and overdiagnosis, making it an essential part of modern prostate cancer testing.

    The study influenced global guidelines, making mpMRI a standard test for suspected prostate cancer.


    NHS Diagnostic Pathway

    Please click below to view the official NHS pathway for diagnosing prostate cancer, developed as a result of the PROMIS trial. 

    Key point informed by the trial - men need to have an MRI before biopsy to confirm prostate cancer.