The “Is mpMRI Enough” or IMRIE Study: A Multicentre Evaluation of Prebiopsy Multiparametric Magnetic Resonance Imaging Compared with Biopsy

Abstract

BackgroundMultiparametric magnetic resonance imaging (mpMRI) is now recommended pre-biopsy in numerous healthcare regions based on the findings of high-quality studies from expert centres. Concern remains about reproducibility of mpMRI to rule-out clinically significant prostate cancer (csPCa) in real-world settings. ObjectiveTo assess the diagnostic performance of mpMRI for csPCa in a real-world setting. Design, Setting, and ParticipantsA multicentre, retrospective cohort study including men referred with a raised PSA or abnormal digital rectal exam who had undergone mpMRI followed by transrectal or transperineal biopsy. Patients could be biopsy naïve or have had previous negative biopsies. Outcome Measurements and Statistical AnalysisThe primary definition for csPCa was defined as ISUP Grade Group 2 or higher (any Gleason >/=7); the accuracy for other definitions was also evaluated. Results and LimitationsAcross 10 sites 2642 men were included (January/2011-November/2018). Mean age and PSA were 65.3 years (SD 7.8 years) and 7.5ng/ml (SD 3.3ng/ml). 35.9% had a 'negative' MRI' (score 1-2). 51.9% underwent transrectal biopsy and 48.1% had transperineal biopsy; with 43.4% diagnosed with csPCa overall. The sensitivity and negative predictive value (NPV) for 5 ISUP GG >/=2 were 87.3% and 87.5%, respectively. The NPV was 87.4% and 88.1% for men undergoing transrectal and transperineal biopsy, respectively. Specificity and positive predictive value of MRI were 49.8% and 49.2%, respectively. The sensitivity and NPV increased to 96.6% and 90.6% when a PSA-density threshold 0.15ng/ml/ml was used in MRI scores 1-2; these metrics increased to 97.5% and 91.2%, respectively, for PSA density 0.12ng/ml/ml. ISUP GG >/=3 (Gleason >/=4+3) was found in 2.4% (15/617) of men with MRI score 1-2. They key limitation of this study is the heterogeneity and retrospective nature of the data. ConclusionsmpMRI when used in real-world settings is able to accurately rule-out csPCa suggesting that about one-third of men might avoid an immediate biopsy. Men should be counselled about the risk of missing some significant cancers.

Identifying Risk Factors for MRI-Invisible Prostate Cancer in Patients Undergoing Transperineal Saturation Biopsy

“…Stonier et al state that the sensitivity and NPV of transrectal and transperineal biopsy increased to 96.6% and 90.6%, respectively, when a PSA density threshold of 0.15ng/mL/mL was used in nMRI (scores 1–2). 27 Furthermore, Kuhlmann et al identified black race and PSA density as risk factors for the presence of nMRI prostate cancer. 15 Our work indicates that an independent risk factor for csPCa is a smaller prostate gland volume.…”

mpMRI of the Prostate (MR-Prostatography): Updated Recommendations of the DRG and BDR on Patient Preparation and Scanning Protocol

“…The risk of developing prostate cancer correlates positively with age, PSA level, PSA density, positive family history and palpation findings [1]. It has been shown that consideration of this patientspecific information in addition to the results of mpMRI of the prostate is associated with higher predictive accuracy for the presence of prostate cancer, lower number of negative biopsies, higher staging accuracy, and higher predictive accuracy for upgrading biopsy results [2][3][4][5][6].…”

A multifaceted approach to quality in the MRI-directed biopsy pathway for prostate cancer diagnosis

“…These advantages minimize the harms of unnecessary biopsies, over-diagnoses, and over-treatments [9]. These benefits are related to the consistent high negative predictive value (NPV) and sensitivity of MRI for PCa detection [10,11] that enable the reliable "ruling-out" of csPCa without needing biopsies [7,12]. A recent meta-analysis of 36 studies including more than 5000 biopsy-naïve men had an NPV of 91% (95% CI 88-96%), meaning that 1 in 10 men with International Society of Uropathology (ISUP) Gleason Grade (GG) ≥ 2 remained undiagnosed [10].…”

“…We must remember that most of the prospective level 1 evidence studies used for guideline development were performed in high-volume expert centers [2,5,6]. However, "real-world" studies show similar NPVs, despite heterogeneities in disease prevalence, MRI scanners, and expertise of radiologists, urologists, and pathologists [1,3,8,10,11]. These concordant data reenforced the guideline recommendations to use MRI-negative results for avoiding prostate biopsies, with appropriate clinical caveats and safety-nets protocols [13][14][15].…”

“…On the other hand, patients with PI-RADS 5 category scores have higher csPCa detection rates of 75% (95% CI, 73-78%) [21]. Next to PI-RADS category biopsy thresholds, the variable PPV is related to patient selections, disease prevalence rates, and radiological factors, and whether clinical factors such as volume-normalized PSA density are used for biopsy decisions [11,22]. Importantly, urologist expertise, their biopsy equipment, and the methods used including whether systematic biopsy cores in addition to targeted cores are obtained [23] affect csPCa detection rates, as do prostate gland volumes, lesion numbers, their sizes and shapes, and their intraprostatic locations.…”