Performance of multiparametric MRI in men at risk of prostate cancer before the first biopsy: A paired validating cohort study using template prostate mapping biopsies as the reference standard - Abstract

Background: Multiparametric magnetic resonance imaging (mpMRI) has the potential to serve as a non-invasive triage test for men at risk of prostate cancer.

Our objective was to determine the performance characteristics of mpMRI in men at risk before the first biopsy using 5 mm template prostate mapping (TPM) as the reference standard.

Methods: One hundred and twenty-nine consecutive men with clinical suspicion of prostate cancer, who had no prior biopsy, underwent mpMRI (T1/T2-weighted, diffusion-weighting, dynamic contrast enhancement) followed by TPM. The primary analysis used were as follows: (a) radiological scores of suspicion of ≥3 attributed from a five-point ordinal scale, (b) a target condition on TPM of any Gleason pattern ≥4 and/or a maximum cancer core length of ≥4 mm and (c) two sectors of analysis per prostate (right and left prostate halves). Secondary analyses evaluated the impact of changing the mpMRI score threshold to ≥4 and varying the target definition for clinical significance.

Results: One hundred and forty-one out of 258 (55%) sectors of analysis showed 'any cancer' and 77/258 (30%) had the target histological condition for the purpose of deriving the primary outcome. Median (with range) for age, PSA, gland volume and number of biopsies taken were 62 years (41-82), 5.8 ng ml-1 (1.2-20), 40 ml (16-137) and 41 cores (20-93), respectively. For the primary outcome sensitivity, specificity, positive and negative predictive values and area under the receiver-operating curve (with 95% confidence intervals) were 94% (88-99%), 23% (17-29%), 34% (28-40%), 89% (79-98%) and 0.72 (0.65-0.79), respectively.

Conclusions: MpMRI demonstrated encouraging diagnostic performance characteristics in detecting and ruling out clinically significant prostate cancer in men at risk, who were biopsy naive.

Written by:
Abd-Alazeez M, Kirkham A, Ahmed HU, Arya M, Anastasiadis E, Charman SC, Freeman A, Emberton M.   Are you the author?
Department of Urology, University College London Hospitals NHS Foundation Trust, London, UK; Department of Urology, Faculty of Medicine, Fayoum University, Fayoum, Egypt.

Reference: Prostate Cancer Prostatic Dis. 2013 Oct 15. Epub ahead of print.
doi: 10.1038/pcan.2013.43

PubMed Abstract
PMID: 24126797 Prostate Cancer Section