There is growing interest to implement multiparametric magnetic resonance imaging (mpMRI) and MR-guided biopsy (MRGB) for biopsy-naïve men with suspected prostate cancer. Primary objective was to compare and evaluate an MRI pathway and a transrectal ultrasound-guided biopsy (TRUSGB) pathway in biopsy-naïve men with prostate-specific antigen levels of ≥3ng/ml. A prospective, multicenter, powered, comparative effectiveness study included 626 biopsy-naïve patients (from February 2015 to February 2018). All patients underwent prebiopsy mpMRI followed by systematic TRUSGB. Men with suspicious lesions on mpMRI also underwent MRGB prior to TRUSGB. MRGB was performed using the in-bore approach. Clinically significant prostate cancer (csPCa) was defined as grade group ≥2 (Gleason score ≥3+4) in any core. The main secondary objectives were the number of men who could avoid biopsy after nonsuspicious mpMRI, the number of biopsy cores taken, and oncologic follow-up. Differences in proportions were tested using McNemar's test with adjusted Wald confidence intervals for differences of proportions with matched pairs. The MRI pathway detected csPCa in 159/626 (25%) patients and insignificant prostate cancer (insignPCa) in 88/626 patients (14%). TRUSGB detected csPCa in 146/626 patients (23%) and insignPCa in 155/626 patients (25%). Relative sensitivity of the MRI pathway versus the TRUSGB pathway was 1.09 for csPCa (p=0.17) and 0.57 for insignPCa (p<0.0001). The total number of biopsy cores reduced from 7512 to 849 (-89%). The MRI pathway enabled biopsy avoidance in 309/626 (49%) patients due to nonsuspicious mpMRI. Immediate TRUSGB detected csPCa in only 3% (10/309) of these patients, increasing to 4% (13/309) with 1-yr follow-up. At the same time, TRUSGB would overdetect insignPCa in 20% (63/309). "Focal saturation" by four additional perilesional cores to MRGB improved the detection of csPCa in 21/317 (7%) patients. Compared with the literature, our proportion of nonsuspicious mpMRI cases is significantly higher (27-36% vs 49%) and that of equivocal cases is lower (15-28% vs 6%). This is probably due to the high-quality standard in this study. Therefore, a limitation is the duplication of these results in less experienced centers. In biopsy-naïve men, the MRI pathway compared with the TRUSGB pathway results in an identical detection rate of csPCa, with significantly fewer insignPCa cases. In this high-quality standard study, almost half of men have nonsuspicious MRI, which is higher compared with other studies. Not performing TRUS biopsy is at the cost of missing csPCa only in 4%. We compared magnetic resonance imaging (MRI) with MRI-guided biopsy against standard transrectal ultrasound biopsy for the diagnosis of prostate cancer in biopsy-naïve men. Our results show that patients can benefit from MRI because biopsy may be omitted in half of men, and fewer indolent cancers are detected, without compromising the detection of harmful disease. Men also need fewer needles to make a diagnosis.

To make magnetic resonance imaging (MRI) more accessible to men at risk of high-grade prostate cancer (PCa), there is a need for quicker, simpler, and less costly MRI protocols. To compare the diagnostic performance of monoplanar ("fast" biparametric MRI [bp-MRI]) and triplanar noncontrast bp-MRI with that of the current contrast-enhanced multiparametric MRI (mp-MRI) in the detection of high-grade PCa in biopsy-naïve men. A prospective, multireader, head-to-head study included 626 biopsy-naïve men, between February 2015 and February 2018. Men underwent prebiopsy contrast-enhanced mp-MRI. Prior to biopsy, two blinded expert readers subsequently assessed "fast" bp-MRI, bp-MRI, and mp-MRI. Thereafter, systematic transrectal ultrasound-guided biopsies (SBs) were performed. Men with suspicious mp-MRI (Prostate Imaging Reporting and Data System 3-5 lesions) also underwent MR-in-bore biopsy (MRGB). Primary outcome was the diagnostic performance of each protocol for the detection of high-grade PCa. Secondary outcomes included the difference in biopsy avoidance, detection of low-grade PCa, acquisition times, decision curve analyses, inter-reader agreement, and direct costs. Results from combined MRGB and SB were used as the reference standard. High-grade PCa was defined as grade ≥2. Sensitivity for high-grade PCa for all protocols was 95% (180/190; 95% confidence interval [CI]: 91-97%). Specificity was 65% (285/436; 95% CI: 61-70%) for "fast" bp-MRI and 69% (299/436; 95% CI: 64-73%) for bp-MRI and mp-MRI. With fast bp-MRI, 0.96% (6/626) more low-grade PCa was detected. Biopsy could be avoided in 47% for the fast bp-MRI and in 49% for the bp-MRI and mp-MRI protocols. Fast bp-MRI and bp-MRI can be performed in 8 and 13min, respectively, instead of 16min at lower direct costs. Inter-reader agreement was 90% for fast bp-MRI protocol and 93% for bp-MRI protocol. A main limitation is the generalizability of these results in less experienced centers. Short MRI protocols can improve prostate MRI accessibility at a lower direct cost. For fast bp-MRI, this is at the cost of ∼2% more biopsies and ∼1% more overdetection of low-grade PCa. In order to implement this technique in nonexpert, low-volume, lower-field-strength scanners, further prospective studies have to be performed. We compared the value of three different magnetic resonance imaging (MRI) protocols for the detection of prostate cancer in men with elevated prostate-specific antigen levels. Our results show that, when used in expert centers, shorter MRI protocols do not compromise the detection of harmful disease. This increases MRI capacity at lower direct costs.

Acquiring multiparametric magnetic resonance images of the prostate is not a simple "push-button" approach. To show how image acquisition of prostate multiparametric Magnetic Resonance Imaging (mpMRI) can be optimized. Image protocols, magnetic field strength choice, and the use of receiver coils are discussed. In addition, patient preparation and the recognition, prevention, and mitigation of artifacts are evaluated. Based on expert prostate MRI technologists (MRI radiographers) opinion, the optimal protocol is reviewed, and potential artifacts are determined. The entire acquisition process is presented from initial patient preparation until the end of the imaging. The choice of the used equipment, pulse sequences, and prevention of patient- and imaging-related artifacts are presented. This will be shown in individual patients. Although the Prostate Imaging Reporting and Data System guidelines (2012 and 2016) describe minimal and optimal acquisition protocols for prostate mpMRI, these standards are not always met in daily practice. A major challenge in mpMRI is to obtain high image quality and reduce its variability for radiologic interpretations. A summary of evidence and guidelines for the acquisition of mpMRI of the prostate can set a basic guideline to reduce these variabilities. This article and an accompanying video can be used as a guide by MRI technologists (MRI radiographers) to improve their image acquisitions by optimizing protocols, magnetic field strength choice, and use of receiver coils. We also discuss patient preparation and the recognition, prevention, and mitigation of artifacts. In this first surgery-in-motion contribution, we will show how optimized image acquisition is performed to detect prostate cancer. Both MRI-dependent and patient related factors are discussed.

In the past 15 years, encouraging clinical results for the detection of small lymph node metastases was obtained by the use of Combidex‐enhanced MRI (CEM, also known as magnetic resonance lymphography). Withdrawal of the European Medicines Agency approval application by the manufacturer made it impossible for patients to benefit from this agent; a loss, especially for men with prostate cancer. Current conventional imaging techniques are not as accurate as CEM is, thus a surgical diagnostic exploration (extended lymph node dissection) is still the preferred technique to evaluate the lymph nodes, resulting in peri‐ and postoperative complications. In 2013, the Radboud University Medical Center (Radboudumc) obtained all licenses and documentation for the production process of Combidex (ferumoxtran‐10), and manufactured the contrast agent under supervision of the Department of Pharmacy. Since 2014, 310 men with prostate cancer have been examined with CEM in the Radboudumc. Within this cohort, seven minor possibly contrast‐related adverse effects were observed after administration of Combidex. As the contrast agent is now back again in the Netherlands, this review highlights the working mechanism, previous results, observed side effects since the reintroduction, and the future perspectives for Combidex. WIREs Nanomed Nanobiotechnol 2018, 10:e1471. doi: 10.1002/wnan.1471This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease

Background: Risk stratification in men with suspicion of prostate cancer (PCa) requires reliable diagnostic tests, not only to identify high-grade PCa, also to minimize the overdetection of low-grade PCa, and reduction of “unnecessary” prostate MRIs and biopsies. This study aimed to evaluate the SelectMDx test to detect high-grade PCa in biopsy-naïve men. Subsequently, to assess combinations of SelectMDx test and multi-parametric (mp) MRI and its potential impact on patient selection for prostate biopsy. Methods: This prospective multicenter diagnostic study included 599 biopsy-naïve patients with prostate-specific antigen level ≥3 ng/ml. All patients underwent a SelectMDx test and mpMRI before systematic transrectal ultrasound-guided biopsy (TRUSGB). Patients with a suspicious mpMRI also had an in-bore MR-guided biopsy (MRGB). Histopathologic outcome of TRUSGB and MRGB was used as reference standard. High-grade PCa was defined as ISUP Grade Group (GG) ≥ 2. The primary outcome was the detection rates of low- and high-grade PCa and number of biopsies avoided in four strategies, i.e., (1) SelectMDx test-only, (2) mpMRI-only, (3) SelectMDx test followed by mpMRI when SelectMDx test was positive (conditional strategy), and (4) SelectMDx test and mpMRI in all (joint strategy). A positive SelectMDx test outcome was a risk score of ≥−2.8. Decision curve analysis (DCA) was performed to assess clinical utility. Results: Prevalence of high-grade PCa was 31% (183/599). Thirty-eight percent (227/599) of patients had negative SelectMDx test in whom biopsy could be avoided. Low-grade PCa was not detected in 35% (48/138) with missing 10% (18/183) high-grade PCa. Yet, mpMRI-only could avoid 49% of biopsies, not detecting 4.9% (9/183) of high-grade PCa. The conditional strategy reduces the number of mpMRIs by 38% (227/599), avoiding biopsy in 60% (357/599) and missing 13% (24/183) high-grade PCa. Low-grade PCa was not detected in 58% (80/138). DCA showed the highest net benefit for the mpMRI-only strategy, followed by the conditional strategy at-risk thresholds >10%. Conclusions: SelectMDx test as a risk stratification tool for biopsy-naïve men avoids unnecessary biopsies in 38%, minimizes low-grade PCa detection, and misses only 10% high-grade PCa. Yet, using mpMRI in all patients had the highest net benefit, avoiding biopsy in 49% and missing 4.9% of high-risk PCa. However, if mpMRI availability is limited or expensive, using mpMRI-only in SelectMDx test positive patients is a good alternative strategy.

There is large variability among radiologists in their detection of clinically significant (cs) prostate cancer (PCa) on multiparametric magnetic resonance imaging (mpMRI). To reduce the interpretation variability and achieve optimal accuracy in assessing prostate mpMRI. How the interpretation of mpMRI can be optimized is demonstrated here. Whereas part 1 of the "surgery-in-motion" paper focused on acquisition, this paper shows the correlation between (ab)normal prostate anatomical structures and image characteristics on mpMRI, and how standardized interpretation according to Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) should be performed. This will be shown in individual patients. To detect csPCa, three mpMRI "components" are used: "anatomic" T2-weighted imaging, "cellular-density" diffusion-weighted imaging, and "vascularity" dynamic contrast-enhanced MRI. Based on PI-RADS v2, the accompanying video shows how mpMRI interpretation is performed. Finally, the role of mpMRI in detecting csPCa is briefly discussed and the main features of the recently introduced PI-RADS v2.1 are evaluated. With PI-RADS v2, it is possible to quantify normal and abnormal anatomical structures within the prostate based on its imaging features of the three mpMRI "components." With this knowledge, a more objective evaluation of the presence of a csPCa can be performed. However, there still remains quite some space to reduce interobserver variability. For understanding the interpretation of mpMRI according to PI-RADS v2, knowledge of the correlation between imaging and (ab)normal anatomical structures on the three mpMRI components is needed. This second surgery-in-motion contribution shows what structures can be recognized on prostate magnetic resonance imaging (MRI). How a radiologist performs his reading according to the so-called Prostate Imaging Reporting and Data System criteria is shown here. The main features of these criteria are summarized, and the role of prostate MRI in detecting clinically significant prostate cancer is discussed briefly.