Multiparametric Magnetic-Resonance to Confirm Eligibility to an Active Surveillance Program for Low-Risk Prostate Cancer: Intermediate Time Results of a Third Referral High Volume Centre Active Surveillance Protocol

Abstract

Background: To evaluate the role of confirmatory multiparametric magnetic resonance imaging (mpMRI) of the prostate at the time of Active Surveillance (AS) enrollment to reduce disease misclassification. Materials: From 2012 to 2016, 383 patients with low-risk disease respecting Prostate Cancer Research International AS criteria underwent confirmatory 1.5-T mpMRI. AS was proposed to patients with Prostate Imaging and Report and Data System (PI-RADS) score ≤3 and no extraprostatic extension (EPE), whereas patients with PI-RADS score ≥4 and/or EPE were treated actively. Kaplan-Meier analyses quantified progression-free survival (PFS) in patients enrolled in the AS program. Logistic regression analyses tested the association between confirmatory mpMRI and clinically significant prostate cancer (csPCa) at radical prostatectomy (RP). Diagnostic performance of mpMRI was calculated in patients submitted to immediate RP. Results: PFS rate was 99, 90 and 86% at 1, 2 and 3 years respectively. At multivariable analysis, PI-RADS 3, PI-RADS 4, PI-RADS 5 and EPE increased the probability of having csPCa at immediate RP (PI-RADS 3 [OR] 1.2, p = 0.26; PI-RADS 4 [OR] 5.1, p = 0.02; PI-RADS 5 [OR] 6.7; p = 0.009; EPE [OR] 11.8, p < 0.001). Confirmatory mpMRI showed sensibility, specificity, positive predictive value and negative predictive value of 85, 55, 68 and 76% respectively. Conclusions: MpMRI at the time of AS enrollment reduces the misclassification rate of csPCa. We suggest to perform target biopsies in patients with PI-RADS score 3 and 4 lesions.

Current Role of Multiparametric MRI and MRI Targeted Biopsies for Prostate Cancer Diagnosis in Germany: A Nationwide Survey

“…While evidence has mostly been generated retrospectively, an initial analysis concluded that stable findings on mpMRI were predictive of stable Gleason score resulting in fewer biopsies for patients on AS [10]. Furthermore, mpMRI at the time of AS enrollment reduces the misclassification rate of csPCa, and therefore MRtb should be performed in patients with PI-RADS ≥3 [11]. Consequently, the German S3 guideline recommends the use of mpMRI for AS patients [12], and therefrom, application of mpMRI might further increase in Germany for these particular patients.…”

MRI-targeted prostate biopsy: the next step forward!

“…mpMRI provides additional information compared to other imagistic examination. Firstly, it evaluates the extraprostatic extension (EPE), being observed that in those with extraprostatic extension the risk of csPCa is 12 times higher, therefore a more aggressive option is chosen [ 68 ]. Secondly, targeted biopsy based on mpMRI reclassified up 10% of patients considered eligible for AS based on SBx [ 69 ], with Fus-TBx upgrading up to 24% of SBx results [ 70 ].…”

“…Multiparametric MRI can play a role in the reevaluation of patients under AS, with the possibility to avoid re-biopsy in patients with PIRADS ≤ 3 lesions and no sign of extra-prostatic extension [ 68 ]. PIRADS score is an independent predictor of csPCa in patients benefiting from AS [ 71 ].…”

“…PIRADS score is an independent predictor of csPCa in patients benefiting from AS [ 71 ]. However, in case of repeated negative mpMRI, biopsy cannot be ruled out because a low risk of csPCa still persists [ 68 ]. TBx performs better in the follow-up evaluation of patients under AS compared with SBx [ 65 , 68 ].…”

Predicting Insignificant Prostate Cancer: Analysis of the Pathological Outcomes of Candidates for Active Surveillance according to the Pre-International Society of Urological Pathology (Pre-ISUP) 2014 Era Versus the Post-ISUP2014 Era

“…In an effort to reduce such misclassification, the use of other modalities such as multiparametric magnetic resonance imaging (mpMRI) in combination with the AS protocol is currently being investigated. Although mpMRI might be a promising tool for selecting AS candidates, some limitations remain with regard to its sensitivity and specificity [ 8 9 10 11 12 13 14 15 16 ].…”