Objectives
This study aims to define consensus-based criteria for acquiring and reporting prostate MRI and establishing prerequisites for image quality.
Methods
A total of 44 leading urologists and ...urogenital radiologists who are experts in prostate cancer imaging from the European Society of Urogenital Radiology (ESUR) and EAU Section of Urologic Imaging (ESUI) participated in a Delphi consensus process. Panellists completed two rounds of questionnaires with 55 items under three headings: image quality assessment, interpretation and reporting, and radiologists’ experience plus training centres. Of 55 questions, 31 were rated for agreement on a 9-point scale, and 24 were multiple-choice or open. For agreement items, there was consensus agreement with an agreement ≥ 70% (score 7–9) and disagreement of ≤ 15% of the panellists. For the other questions, a consensus was considered with ≥ 50% of votes.
Results
Twenty-four out of 31 of agreement items and 11/16 of other questions reached consensus. Agreement statements were (1) reporting of image quality should be performed and implemented into clinical practice; (2) for interpretation performance, radiologists should use self-performance tests with histopathology feedback, compare their interpretation with expert-reading and use external performance assessments; and (3) radiologists must attend theoretical and hands-on courses before interpreting prostate MRI. Limitations are that the results are expert opinions and not based on systematic reviews or meta-analyses. There was no consensus on outcomes statements of prostate MRI assessment as quality marker.
Conclusions
An ESUR and ESUI expert panel showed high agreement (74%) on issues improving prostate MRI quality. Checking and reporting of image quality are mandatory. Prostate radiologists should attend theoretical and hands-on courses, followed by supervised education, and must perform regular performance assessments.
Key Points
• Multi-parametric MRI in the diagnostic pathway of prostate cancer has a well-established upfront role in the recently updated European Association of Urology guideline and American Urological Association recommendations
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• Suboptimal image acquisition and reporting at an individual level will result in clinicians losing confidence in the technique and returning to the (non-MRI) systematic biopsy pathway. Therefore, it is crucial to establish quality criteria for the acquisition and reporting of mpMRI
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• To ensure high-quality prostate MRI, experts consider checking and reporting of image quality mandatory. Prostate radiologists must attend theoretical and hands-on courses, followed by supervised education, and must perform regular self- and external performance assessments
.
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.
In biopsy-naïve patients, a magnetic resonance imaging (MRI) pathway compared with a transrectal ultrasound-guided biopsy pathway significantly reduces the detection rate of insignificant prostate cancer without impairing the detection rate of clinically significant prostate cancer. There is a potential to reduce the number of men requiring biopsy after nonsuspicious MRI to half, with an acceptable underdetection rate of 4%.
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.
Acquisition of magnetic resonance (MR) images is not a “push-button” technique. Only with adequate knowledge of modern state-of-the-art MR scanners, new optimized acquisition protocols, and optimal patient preparation, the MRI technologist (MRI radiographer) will make adequate prostate multiparametric MR images. Optimal images are needed for the radiologist to make interpretation better and easier.
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.
Short magnetic resonance imaging (MRI) protocols improves prostate MRI accessibility at a lower direct-cost: twice as fast bi-parametric MRI is as accurate as multi-parametric MRI, only at the cost of 2% more biopsies and 1% more over-detection of low-grade prostate cancer.
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.1471
This article is categorized under:
Diagnostic Tools > In Vivo Nanodiagnostics and Imaging
Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease
Combidex‐enhanced magnetic resonance imaging (MRI) at 3 T of a 53‐year‐old patient with recurrent prostate cancer after radical prostatectomy and radiotherapy (PSA‐level 3.9 ng/mL). Twenty‐seven hours after administration of Combidex benign lymph nodes have accumulated the contrast agent, becoming black on a three‐dimensional (3D) iron‐sensitive MRI scan. Metastatic lymph nodes retain signal and therefore stay white. A large (7 mm) metastatic lymph node is visible on Combidex‐enhanced MRI as a white spherical structure in two orthogonal planes through the node blue circles in coronal (a) and axial images (b). A smaller metastatic white node (2–3 mm) is indicated with red circles in the coronal (c) and axial (d) reconstructions (orthogonal planes through the node of interest) of the 3D data set. The other small spherical structures are blood vessels, best appreciated when scrolling through the 3D image data set.
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.
This paper provides insight into what structures of normal and abnormal prostates are visible with multiparametric magnetic resonance imaging (mpMRI). To detect clinically significant prostate cancer, three mpMRI “components” must be used: “anatomic” T2-weighted imaging, “cellular density” diffusion-weighted imaging, and “vascularity” dynamic contrast–enhanced MRI. Based on these images, mpMRI interpretation according to the Prostate Imaging Reporting and Data System is done.
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.
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.
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%.
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.
This surgery-in-motion contribution shows that transperineal magnetic resonance–ultrasound fusion guided biopsy in men with suspected prostate cancer is well tolerated using local anesthesia in an ...ambulatory setting. The detection rates of clinically significant cancer are high, and even without prophylactic antibiotics, the risk of infectious complication is low.
Transperineal magnetic resonance imaging–transrectal ultrasound fusion guided biopsy (MFGB) is an increasingly popular technique due to increasing rates of biopsy-related infections. However, its widespread implementation has been hampered by the supposed necessity of epidural or general anesthesia.
To demonstrate the technique, feasibility, and results of transperineal MFGB under local anesthesia, in an ambulatory setting without the administration of prophylactic antibiotics.
This single-center study enrolled consecutive biopsy-naïve men with a clinical suspicion of prostate cancer into a prospective database between November 2015 and November 2020. Men with Prostate Imaging Reporting and Data System (PI-RADS) version 2 scores 3–5 underwent transperineal MFGB.
Transperineal MFGB was performed in an ambulatory setting under local anesthesia by a single operator.
Procedure-associated adverse events were recorded. Patient discomfort during both the local anesthesia and the biopsy procedure was determined using a visual analogic scale (0–10). Detection rates of grade group (GG) ≥2 prostate cancer and the proportion of men with GG 1 cancer were assessed.
A total of 1097 eligible men underwent transperineal MFGB. The complication rate was 0.73% (8/1097); complications comprised five (0.46%) urinary tract infections including one hospitalization and three (0.27%) urinary retentions. In 735 men, the median pain scores were 2 (interquartile range IQR 2–3) for the local anesthesia procedure and 1 (IQR 0-2) for the biopsy. Prostate cancer was detected in 84% (926/1097) of men; 66% (723/1097) had GG ≥2 and 19% (203/1097) GG 1.
Transperineal MFGB can safely be performed as an outpatient procedure under local anesthesia in an ambulatory setting. The detection rate of clinically significant prostate cancer is high, and biopsy is well tolerated. Although no antibiotic prophylaxis was used, the rate of infectious complications is practicably negligible.
This article shows how tissue samples (biopsies) can accurately be obtained from suspicious regions seen on prostate magnetic resonance imaging via needles inserted in the perineum (skin between the scrotum and the anus) in men with suspected prostate cancer. This technique appears to be very well tolerated under local anesthesia and has a lower risk of infection without antibiotic prophylaxis than the more common biopsy route through the rectum, with antibiotics.