The added value of diffusion-weighted images and dynamic contrast-enhancement in multi-parametric MRI for the detection of clinically significant prostate cancer in the PICTURE trial.BJU Int 2019BI
To determine the additional diagnostic value of diffusion-weighted imaging (DWI) and dynamic contrast-enhanced (DCE) imaging in men requiring a repeat biopsy within the PICTURE study.
PATIENTS AND METHODS
PICTURE was a paired-cohort confirmatory study in which 249 men who required further risk stratification following a previous non-MRI guided TRUS biopsy underwent a 3-Tesla mpMRI consisting of T2W, DWI and DCE followed by transperineal template prostate mapping (TPM) biopsy. Each mpMRI was reported using a LIKERT score in a sequential blinded manner to generate scores for T2W, T2W+DWI and T2W+DWI+DCE. Area under the receiver operating characteristic (AUROC) fanalysis was performed to compare the diagnostic accuracy of each combination. The threshold for a positive mpMRI was set as a LIKERT score >/=3. Clinically significant prostate cancer was analysed across a range of definitions including UCL/Ahmed Definition 1 (primary definition), UCL/Ahmed Definition 2, any Gleason >/=3+4 and any Gleason >/=4+3.
Of 249, sequential MRI reporting was available for 246. There was a higher rate of equivocal lesions (44.6%) using T2W alone compared to the addition of DWI (23.9%) and DCE (19.8%). Using the primary definition of clinically significant disease, there was no significant difference in the overall accuracy between T2W at AUROC 0.74 (95% CI 0.68-0.80), T2W+DWI at 0.76 (95% CI 0.71-0.82) and T2W+DWI+DCE at 0.77 (95% CI 0.71-0.82) (p=0.55). The AUROCs remained comparable using other definitions of clinically significant disease including UCL/Ahmed 2 (p=0.79), Gleason >/=3+4 (p=0.53) and Gleason >/=4+3 (p=0.53).
Using a 3T MRI, a high level of diagnostic accuracy can be achieved using T2W as a single parameter in men with a prior biopsy. However, such a strategy can lead to a higher rate of equivocal lesions.