Category: Imaging & Image Guided Therapy: New Therapies

MP4-10 - What Is The Negative Predictive Value of mpMRI in Excluding Significant Prostate Cancer at Biopsy? Results from a Regional Cancer Centre

Fri, Sep 21
10:00 AM - 12:00 PM

Introduction & Objective :

Pre-biopsy multiparametric MRI (mpMRI) is reported to have a negative predictive value (NPV) of 89% in prostate cancer diagnosis. We aimed to determine the negative predictive value of mpMRI alone and in combination with PSA density for clinically significant prostate cancer in men undergoing prostate biopsy at our institution. 


Methods :

A retrospective review of consecutive biopsy-naive patients undergoing 1.5T or 3T pre-biopsy mpMRI from October 2015 to January 2018 was performed. Men with negative mpMRI underwent a minimum of 12-core systematic transrectal ultrasound-guided biopsy. Clinical features, cancer detection rates and negative predictive values are summarized. Clinically significant cancer was defined as the presence of a single biopsy core indicating Gleason score 3+4 disease or greater.


Results :

600 mpMRIs were performed. Of these, 279 (46%) were PIRADS 1 or 2.

Overall, cancer was detected in 72/279 (26%) men with negative mpMRI. Clinically significant prostate cancer was detected in 46/279 (16%).


Gleason 3+3= 26/279 (9.3%)

Gleason 3+4= 36/279 (12.9%)

Gleason 4+3= 4/279 (1.4%)

Gleason 3+5= 4/479 (1.4%)

Gleason 4+5= 2/279 (0.7%)


The NPV for all cancers was 74% and for clinically significant prostate cancer was 84%.

Using a PSA density cut-off of 0.15ng/ml/ml and 0.10ng/ml/ml in combination with a negative mpMRI increased the NPV for clinically significant cancer to 89% and 93% respectively. 


Conclusions :

At our instituition, a negative pre-biopsy mpMRI confers a NPV of 84% on systematic transrectal biopsy for clinically significant prostate cancer. The NPV increased to 93% when the PSA density was 0.10 ng/ml/ml or less.  This is similar to other published series. We are now able to inform our patients with locally audited data about their risk of missing significant cancer and suggest that all centres audit their own mpMRI use. 

Niyati Lobo

Urology Registrar
East Kent Hospitals University NHS Foundation Trust
Canterbury, England, United Kingdom

Iain Morrison

Consultant Radiologist
East Kent Hospitals University NHS Foundation Trust
Canterbury, England, United Kingdom

Muhammad Eraibey

Consultant Radiologist
East Kent Hospitals University NHS Foundation Trust
Canterbury, England, United Kingdom

Neophytos Petrides

Urology Specialist Trainee
Kent and Canterbury Hospital
Cambridge, England, United Kingdom

Sashi S. Kommu

Consultant Urological Surgeon
Canterbury Centre for Robotic Urological Surgery. East Kent Hospitals University NHS Foundation Trust.
Canterbury, England, United Kingdom

Milan Thomas

Consultant Urologist
East Kent Hospitals University NHS Foundation Trust
Canterbury, England, United Kingdom

Ben Eddy

Consultant Urologist
East Kent Hospitals University NHS Foundation Trust
Canterbury, England, United Kingdom