Optimal Method for Reporting Prostate Cancer Grade in MRI-targeted Biopsies.

When multiple cores are biopsied from a single magnetic resonance imaging (MRI)-targeted lesion, Gleason grade may be assigned for each core separately or for all cores of the lesion in aggregate. Because of the potential for disparate grades, an optimal method for pathology reporting MRI lesion grade awaits validation. We examined our institutional experience on the concordance of biopsy grade with subsequent radical prostatectomy (RP) grade of targeted lesions when grade is determined on individual versus aggregate core basis. For 317 patients (with 367 lesions) who underwent MRI-targeted biopsy followed by RP, targeted lesion grade was assigned as (1) global Grade Group (GG), aggregated positive cores; (2) highest GG (highest grade in single biopsy core); and (3) largest volume GG (grade in the core with longest cancer linear length). The 3 biopsy grades were compared (equivalence, upgrade, or downgrade) with the final grade of the lesion in the RP, using κ and weighted κ coefficients. The biopsy global, highest, and largest GGs were the same as the final RP GG in 73%, 68%, 62% cases, respectively (weighted κ: 0.77, 0.79, and 0.71). For cases where the targeted lesion biopsy grade scores differed from each other when assigned by global, highest, and largest GG, the concordance with the targeted lesion RP GG was 69%, 52%, 31% for biopsy global, highest, and largest GGs tumors (weighted κ: 0.65, 0.68, 0.59). Overall, global, highest, and largest GG of the targeted biopsy show substantial agreement with RP-targeted lesion GG, however targeted global GG yields slightly better agreement than either targeted highest or largest GG. This becomes more apparent in nearly one third of cases when each of the 3 targeted lesion level biopsy scores differ. These results support the use of global (aggregate) GG for reporting of MRI lesion-targeted biopsies, while further validations are awaited.

Risk of Prostate Cancer after a Negative Magnetic Resonance Imaging Guided Biopsy.

PURPOSE: Magnetic resonance imaging guided biopsy which reveals no cancer may impart reassurance beyond that offered by ultrasound guided biopsy. However, followup of men after a negative magnetic resonance imaging guided biopsy has been mostly by prostate specific antigen testing and reports of followup tissue confirmation are few. We investigated the incidence of clinically significant prostate cancer in such men who, because of persistent cancer suspicion, subsequently underwent a repeat magnetic resonance imaging guided biopsy. MATERIALS AND METHODS: Subjects were all men with a negative initial magnetic resonance imaging guided biopsy who underwent at least 1 further magnetic resonance imaging guided biopsy due to continued clinical suspicion of clinically significant prostate cancer (September 2009 to July 2019). Biopsies were magnetic resonance imaging-ultrasound fusion with targeted and systematic cores. Regions of interest from initial magnetic resonance imaging and any new regions of interest at followup magnetic resonance imaging guided biopsy were targeted. The primary end point was detection of clinically significant prostate cancer (Gleason Grade Group 2 or greater). RESULTS: Of 2,716 men 733 had a negative initial magnetic resonance imaging guided biopsy. Study subjects were 73/733 who underwent followup magnetic resonance imaging guided biopsy. Median (IQR) age and prostate specific antigen density were 64 years (59-67) and 0.12 ng/ml/cc (0.08-0.17), respectively. Baseline PI-RADS® scores were 3 or greater in 74%. At followup magnetic resonance imaging guided biopsy (median 2.4 years, IQR 1.3-3.6), 17/73 (23%) were diagnosed with clinically significant prostate cancer. When followup magnetic resonance imaging revealed a lesion (PI-RADS 3 or greater), clinically significant prostate cancer was found in 17/53 (32%). When followup magnetic resonance imaging was negative (PI-RADS less than 3), cancer was not found (0/20) (p <0.01). Overall 54% of men with PI-RADS 5 at followup magnetic resonance imaging guided biopsy were found to have clinically significant prostate cancer. CONCLUSIONS: Men with negative magnetic resonance imaging following an initial negative magnetic resonance imaging guided biopsy are unlikely to harbor clinically significant prostate cancer and may avoid repeat biopsy. However, when lesions are seen on followup magnetic resonance imaging, repeat magnetic resonance imaging guided biopsy is warranted.

Prostate Imaging-Reporting and Data System Steering Committee: PI-RADS v2 Status Update and Future Directions.

CONTEXT: The Prostate Imaging-Reporting and Data System (PI-RADS) v2 analysis system for multiparametric magnetic resonance imaging (mpMRI) detection of prostate cancer (PCa) is based on PI-RADS v1, accumulated scientific evidence, and expert consensus opinion. OBJECTIVE: To summarize the accuracy, strengths and weaknesses of PI-RADS v2, discuss pathway implications of its use and outline opportunities for improvements and future developments. EVIDENCE ACQUISITION: For this consensus expert opinion from the PI-RADS steering committee, clinical studies, systematic reviews, and professional guidelines for mpMRI PCa detection were evaluated. We focused on the performance characteristics of PI-RADS v2, comparing data to systems based on clinicoradiologic Likert scales and non-PI-RADS v2 imaging only. Evidence selections were based on high-quality, prospective, histologically verified data, with minimal patient selection and verifications biases. EVIDENCE SYNTHESIS: It has been shown that the test performance of PI-RADS v2 in research and clinical practice retains higher accuracy over systematic transrectal ultrasound (TRUS) biopsies for PCa diagnosis. PI-RADS v2 fails to detect all cancers but does detect the majority of tumors capable of causing patient harm, which should not be missed. Test performance depends on the definition and prevalence of clinically significant disease. Good performance can be attained in practice when the quality of the diagnostic process can be assured, together with joint working of robustly trained radiologists and urologists, conducting biopsy procedures within multidisciplinary teams. CONCLUSIONS: It has been shown that the test performance of PI-RADS v2 in research and clinical practice is improved, retaining higher accuracy over systematic TRUS biopsies for PCa diagnosis. PATIENT SUMMARY: Multiparametric magnetic resonance imaging (MRI) and MRI-directed biopsies using the Prostate Imaging-Reporting and Data System improves the detection of prostate cancers likely to cause harm, and at the same time decreases the detection of disease that does not lead to harms if left untreated. The keys to success are high-quality imaging, reporting, and biopsies by radiologists and urologists working together in multidisciplinary teams.

Primary magnetic resonance imaging/ultrasonography fusion-guided biopsy of the prostate.

OBJECTIVE: To examine the performance of a primary magnetic resonance imaging (MRI)/ultrasonography (US) fusion-guided targeted biopsy (TB), and in combination with an added systematic biopsy (SB). PATIENTS AND METHODS: Analysis of 318 consecutive biopsy-naïve men with suspicious multiparametric MRI (mpMRI; Prostate Imaging Reporting and Data System [PI-RADS] score ≥3) undergoing transrectal TB and 10-core SB between January 2012 and December 2016. The indication for performing mpMRI was based on clinical parameters and decided by the treating urologist before admission. TB was performed with a sensor-based MRI/US fusion-guided platform. Clinically significant prostate cancer was defined as Gleason score ≥4 + 3 = 7 (International Society of Urological Pathology Grade [ISUP] grade 3) or maximum cancer core length of ≥6 mm. RESULTS: A median (interquartile range) of 14 (13-14) biopsies per case were taken. The overall cancer detection rate (CDR) was 77% (245/318). The TB alone detected 67% of prostate cancers and the SB alone detected 70%. The PI-RADS dependent CDR for the combination of TB/SB were 38% (21/55), 78% (120/154) and 95% (104/109) for PI-RADS scores of 3/4/5, respectively. Clinically significant prostate cancer was diagnosed by the combination of TB and SB in 195 men (61%) and by TB alone in 163 cases (51%). The number of missed or underestimated prostate cancers with a Gleason score ≥8 for TB alone was 31 (10%, P < 0.001) and 21 (7%, P < 0.001) for SB alone in comparison with the results of the combination of TB and SB. The rate of insignificant prostate cancer was comparable for the combination of TB and SB and TB alone (50/318, 16% vs 50/318, 16%). CONCLUSIONS: Pre-biopsy mpMRI is of incremental value in increasing the detection of clinically significant prostate cancer in biopsy-naïve patients with suspicion of prostate cancer. Combining TB with SB further improved the diagnostic accuracy without increasing the rate of insignificant prostate cancer.

Development of a Nationally Representative Coordinated Registry Network for Prostate Ablation Technologies.

PURPOSE: The accumulation of data through a prospective, multicenter coordinated registry network is a practical way to gather real world evidence on the performance of novel prostate ablation technologies. Urological oncologists, targeted biopsy experts, industry representatives and representatives of the FDA (Food and Drug Administration) convened to discuss the role, feasibility and important data elements of a coordinated registry network to assess new and existing prostate ablation technologies. MATERIALS AND METHODS: A multiround Delphi consensus approach was performed which included the opinion of 15 expert urologists, representatives of the FDA and leadership from high intensity focused ultrasound device manufacturers. Stakeholders provided input in 3 consecutive rounds with conference calls following each round to obtain consensus on remaining items. Participants agreed that these elements initially developed for high intensity focused ultrasound are compatible with other prostate ablation technologies. Coordinated registry network elements were reviewed and supplemented with data elements from the FDA common study metrics. RESULTS: The working group reached consensus on capturing specific patient demographics, treatment details, oncologic outcomes, functional outcomes and complications. Validated health related quality of life questionnaires were selected to capture patient reported outcomes, including the IIEF-5 (International Index of Erectile Function-5), the I-PSS (International Prostate Symptom Score), the EPIC-26 (Expanded Prostate Cancer Index Composite-26) and the MSHQ-EjD (Male Sexual Health Questionnaire for Ejaculatory Dysfunction). Group consensus was to obtain followup multiparametric magnetic resonance imaging and prostate biopsy approximately 12 months after ablation with additional imaging or biopsy performed as clinically indicated. CONCLUSIONS: A national prostate ablation coordinated registry network brings forth vital practice pattern and outcomes data for this emerging treatment paradigm in the United States. Our multiple stakeholder consensus identifies critical elements to evaluate new and existing energy modalities and devices.

Optimizing the Number of Cores Targeted During Prostate Magnetic Resonance Imaging Fusion Target Biopsy.

BACKGROUND: The number of prostate biopsy cores that need to be taken from each magnetic resonance imaging (MRI) region of interest (ROI) to optimize sampling while minimizing overdetection has not yet been clearly elucidated. OBJECTIVE: To characterize the incremental value of additional MRI-ultrasound (US) fusion targeted biopsy cores in defining the optimal number when planning biopsy and to predict men who might benefit from more than two targeted cores. DESIGN, SETTING, AND PARTICIPANTS: This was a retrospective cohort study of MRI-US fusion targeted biopsies between 2015 and 2017. INTERVENTION: MRI-US fusion targeted biopsy in which four biopsy cores were directed to each MRI-targeted ROI. OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS: The MRI-targeted cores representing the first highest Gleason core (FHGC) and first clinically significant cancer core (FCSC; GS≥3+4) were evaluated. We analyzed the frequency of FHGC and FCSC among cores 1-4 and created a logistic regression model to predict FHGC >2. The number of unnecessary cores avoided and the number of malignancies missed for each Gleason grade were calculated via clinical utility analysis. The level of agreement between biopsy and prostatectomy Gleason scores was evaluated using Cohen's κ. RESULTS AND LIMITATIONS: A total of 479 patients underwent fusion targeted biopsy with four individual cores, with 615 ROIs biopsied. Among those, FHGC was core 1 in 477 (76.8%), core 2 in 69 (11.6%), core 3 in 48 (7.6%), and core 4 in 24 men (4.0%) with any cancer. Among men with clinically significant cancer, FCSC was core 1 in 191 (77.8%), core 2 in 26 (11.1%), core 3 in 17 (6.2%), and core 4 in 11 samples (4.9%). In comparison to men with a Prostate Imaging-Reporting and Data System (PI-RADS) score of 5, patients were significantly less likely to have FHGS >2 if they had PI-RADS 4 (odds ratio [OR] 0.287; p=0.006), PI-RADS 3 (OR 0.284; p=0.006), or PI-RADS 2 (OR 0.343; p=0.015). Study limitations include a single-institution experience and the retrospective nature. CONCLUSIONS: Cores 1-2 represented FHGC 88.4% and FCSC 88.9% of the time. A PI-RADS score of 5 independently predicted FHGC >2. Although the majority of cancers in our study were appropriately characterized in the first two biopsy cores, there remains a proportion of men who would benefit from additional cores. PATIENT SUMMARY: In men who undergo magnetic resonance imaging-ultrasound fusion targeted biopsy, the first two biopsy cores diagnose the majority of clinically significant cancers. However, there remains a proportion of men who would benefit from additional cores.

MRI-guided stereotactic neurosurgical procedures in a diagnostic MRI suite: Background and safe practice recommendations.

The development of navigation technology facilitating MRI-guided stereotactic neurosurgery has enabled neurosurgeons to perform a variety of procedures ranging from deep brain stimulation to laser ablation entirely within an intraoperative or diagnostic MRI suite while having real-time visualization of brain anatomy. Prior to this technology, some of these procedures required multisite workflow patterns that presented significant risk to the patient during transport. For those facilities with access to this technology, safe practice guidelines exist only for procedures performed within an intraoperative MRI. There are currently no safe practice guidelines or parameters available for facilities looking to integrate this technology into practice in conventional MRI suites. Performing neurosurgical procedures in a diagnostic MRI suite does require precautionary measures. The relative novelty of technology and workflows for direct MRI-guided procedures requires consideration of safe practice recommendations, including those pertaining to infection control and magnet safety issues. This article proposes a framework of safe practice recommendations designed for assessing readiness and optimization of MRI-guided neurosurgical interventions in the diagnostic MRI suite in an effort to mitigate patient risk. The framework is based on existing clinical evidence, recommendations, and guidelines related to infection control and prevention, health care-associated infections, and magnet safety, as well as the clinical and practical experience of neurosurgeons utilizing this technology.

Comparison of Deep Brain Stimulation Lead Targeting Accuracy and Procedure Duration between 1.5- and 3-Tesla Interventional Magnetic Resonance Imaging Systems: An Initial 12-Month Experience.

BACKGROUND: Interventional magnetic resonance imaging (iMRI) allows deep brain stimulator lead placement under general anesthesia. While the accuracy of lead targeting has been described for iMRI systems utilizing 1.5-tesla magnets, a similar assessment of 3-tesla iMRI procedures has not been performed. OBJECTIVE: To compare targeting accuracy, the number of lead targeting attempts, and surgical duration between procedures performed on 1.5- and 3-tesla iMRI systems. METHODS: Radial targeting error, the number of targeting attempts, and procedure duration were compared between surgeries performed on 1.5- and 3-tesla iMRI systems (SmartFrame and ClearPoint systems). RESULTS: During the first year of operation of each system, 26 consecutive leads were implanted using the 1.5-tesla system, and 23 consecutive leads were implanted using the 3-tesla system. There was no significant difference in radial error (Mann-Whitney test, p = 0.26), number of lead placements that required multiple targeting attempts (Fisher's exact test, p = 0.59), or bilateral procedure durations between surgeries performed with the two systems (p = 0.15). CONCLUSIONS: Accurate DBS lead targeting can be achieved with iMRI systems utilizing either 1.5- or 3-tesla magnets. The use of a 3-tesla magnet, however, offers improved visualization of the target structures and allows comparable accuracy and efficiency of placement at the selected targets.

What is still needed to make focal therapy an accepted segment of standard therapy?

PURPOSE OF REVIEW: Focal therapy is gaining interest and this organ-preserving treatment is heading towards becoming an alternative for the conventional surgery and radiation. The purpose of this review is to determine what evidence is required to make focal therapy a viable option for treatment of localized prostate cancer. RECENT FINDINGS: There is still a lack of high-level evidence for the different focal treatment modalities. The early-stage focal therapy trials are conducted including a various selection of patients and different pretreatment assessment and follow-up, resulting in incomparable data. Recent literature shows it is paramount to extend the amount of biopsies and to alter the way of taking the biopsies with the template-assisted or image-guided approach. To date, multiparametric MRI is the most effective imaging technique in selecting patients for focal therapy. SUMMARY: Focal therapy trials are at the early stage of clinical development, with the majority still being phase I studies. To make focal therapy an accepted segment of standard therapy, it needs to proceed toward phase II and III trials. These trials should be conducted with an effective trial design, which will lead to more comparable oncological, functional and quality of life outcomes. Furthermore, it is essential to improve the localization of tumor foci in order to increase the accuracy of spatial targeting of cancer.

Standards for prostate biopsy.

PURPOSE OF REVIEW: A variety of techniques have emerged for the optimization of prostate biopsy. In this review, we summarize and critically discuss the most recent developments regarding the optimal systematic biopsy and sampling labeling along with multiparametric MRI and magnetic resonance-targeted biopsies. RECENT FINDINGS: The use of 10-12-core-extended sampling protocols increases cancer detection rates compared with traditional sextant sampling and reduces the likelihood that patients will require a repeat biopsy, ultimately allowing more accurate risk stratification without increasing the likelihood of detecting insignificant cancers. As the number of cores increases above 12 cores, the increase in diagnostic yield becomes marginal. However, the limitations of this technique include undersampling, oversampling, and the need for repetitive biopsy. MRI and magnetic resonance-targeted biopsies have demonstrated superiority over systematic biopsies for the detection of clinically significant disease and representation of disease burden, while deploying fewer cores and may have applications in men undergoing initial or repeat biopsy and those with low-risk cancer on or considering active surveillance. SUMMARY: A 12-core systematic biopsy that incorporates apical and far-lateral cores in the template distribution allows maximal cancer detection, avoidance of a repeat biopsy while minimizing the detection of insignificant prostate cancers. MRI-guided prostate biopsy has an evolving role in both initial and repeat prostate biopsy strategies, as well as active surveillance, potentially improving sampling efficiency, increasing the detection of clinically significant cancers, and reducing the detection of insignificant cancers.

Improving detection of clinically significant prostate cancer: magnetic resonance imaging/transrectal ultrasound fusion guided prostate biopsy.

PURPOSE: Given the limitations of prostate specific antigen and standard biopsies for detecting prostate cancer, we evaluated the cancer detection rate and external validity of a magnetic resonance imaging/transrectal ultrasound fusion guided prostate biopsy system used at the National Institutes of Health. MATERIALS AND METHODS: We performed a phase III trial of a magnetic resonance imaging/transrectal ultrasound fusion guided prostate biopsy system with participants enrolled between 2012 and 2013. A total of 153 men consented to the study and underwent 3 Tesla multiparametric magnetic resonance imaging with an endorectal coil for clinical suspicion of prostate cancer. Lesions were classified as low or moderate/high risk for prostate cancer. Magnetic resonance imaging/transrectal ultrasound fusion guided biopsy and standard 12-core prostate biopsy were performed and 105 men were eligible for analysis. RESULTS: Mean patient age was 65.8 years and mean prostate specific antigen was 9.5 ng/ml. The overall cancer detection rate was 62.9% (66 of 105 patients). The cancer detection rate in those with moderate/high risk on imaging was 72.3% (47 of 65) vs 47.5% (19 of 40) in those classified as low risk for prostate cancer (p<0.05). Mean tumor core length was 4.6 and 3.7 mm for fusion biopsy and standard 12-core biopsy, respectively (p<0.05). Magnetic resonance imaging/transrectal ultrasound fusion guided biopsy detected prostate cancer that was missed by standard 12-core biopsy in 14.3% of cases (15 of 105), of which 86.7% (13 of 15) were clinically significant. This biopsy upgraded 23.5% of cancers (4 of 17) deemed clinically insignificant on 12-core biopsy to clinically significant prostate cancer necessitating treatment. CONCLUSIONS: Magnetic resonance imaging/transrectal ultrasound fusion guided biopsy can improve prostate cancer detection. The results of this trial support the external validity of this platform and may be the next step in the evolution of prostate cancer management.

Standards of reporting for MRI-targeted biopsy studies (START) of the prostate: recommendations from an International Working Group.

BACKGROUND: A systematic literature review of magnetic resonance imaging (MRI)-targeted prostate biopsy demonstrates poor adherence to the Standards for the Reporting of Diagnostic Accuracy (STARD) recommendations for the full and transparent reporting of diagnostic studies. OBJECTIVE: To define and recommend Standards of Reporting for MRI-targeted Biopsy Studies (START). DESIGN, SETTING, AND PARTICIPANTS: Each member of a panel of 23 experts in urology, radiology, histopathology, and methodology used the RAND/UCLA appropriateness methodology to score a 258-statement premeeting questionnaire. The collated responses were presented at a face-to-face meeting, and each statement was rescored after group discussion. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Measures of agreement and consensus were calculated for each statement. The most important statements, based on group median score, the degree of group consensus, and the content of the group discussion, were used to create a checklist of reporting criteria (the START checklist). RESULTS AND LIMITATIONS: The strongest recommendations were to report histologic results of standard and targeted cores separately using Gleason score and maximum cancer core length. A table comparing detection rates of clinically significant and clinically insignificant disease by targeted and standard approaches should also be used. It was recommended to report the recruitment criteria for MRI-targeted biopsy, prior biopsy status of the population, a brief description of the MRI sequences, MRI reporting method, radiologist experience, and image registration technique. There was uncertainty about which histologic criteria constitute clinically significant cancer when the prostate is sampled using MRI-targeted biopsy, and it was agreed that a new definition of clinical significance in this setting needed to be derived in future studies. CONCLUSIONS: Use of the START checklist would improve the quality of reporting in MRI-targeted biopsy studies and facilitate a comparison between standard and MRI-targeted approaches.

A diagnostic accuracy meta-analysis of endoanal ultrasound and MRI for perianal fistula assessment.

BACKGROUND: Imaging modalities such as endoanal ultrasound or MRI can be useful preoperative adjuncts before the appropriate surgical intervention for perianal fistulas. OBJECTIVES: We present a systematic review of published literature comparing endoanal ultrasound with MRI for the assessment of idiopathic and Crohn's perianal fistulas. DESIGN: A meta-analysis was performed to obtain pooled values for specificity and sensitivity. SETTINGS: Electronic databases were searched from January 1970 to October 2010 for published studies. PATIENTS AND INTERVENTIONS: Four studies were used in our analysis. There were 241 fistulas in the ultrasound group and 240 in the magnetic resonance group. RESULTS: The combined sensitivity and specificity of magnetic resonance for fistula detection were 0.87 (95% CI: 0.63-0.96) and 0.69 (95% CI: 0.51-0.82). There was a high degree of heterogeneity between studies reporting on MRI sensitivity (df = 3, I = 93%). This compares to a sensitivity and specificity for endoanal ultrasound of 0.87 (95% CI: 0.70-0.95) and 0.43 (95% CI: 0.21-0.69). There was a high degree of heterogeneity between studies reporting on endoanal ultrasound sensitivity (df = 3, I = 92%). CONCLUSIONS: From the available literature, the summarized performance characteristics for MRI and endoanal ultrasound demonstrate comparable sensitivities at detecting perianal fistulas, although the specificity for MRI was higher than that for endoanal ultrasound. Both specificity values are considered to be diagnostically poor, however. The high degree of data heterogeneity and the shortage of applicable studies precludes any firm conclusions being made for clinical practice. Future trials with improved study design (including prospective data collection and consideration of verification bias) may help to further clarify the role of MRI in the assessment and treatment response monitoring of perianal fistulas (particularly in patients with Crohn's disease).

Post-interventional three-dimensional dark blood MRI in the adult with congenital heart disease.

BACKGROUND: Investigate a novel three-dimensional (3D) turbo spin echo (TSE) magnetic resonance imaging (MRI) sequence to assess stented segments in adults with congenital heart disease (CHD) after transcatheter intervention. METHODS: Adults with CHD referred for computed tomography (CT) after transcatheter intervention underwent MR exam with a 3D respiratory gated TSE sequence. Data obtained at the time of the study included type of CHD, radiation dose, length of time between exams, and luminal diameters of stented segments from each exam. Continuous variables were analyzed using Student'st and Bland-Altman plots performed to analyze measurements obtained from both examinations. RESULTS: Eleven patients underwent both examinations. Type of defects included coarctation of the aorta (n=6) and tetralogy of Fallot. Average radiation dose was 19.6 mSv and average time between CT and MRI was 99 ± 160 days. Luminal diameters of stented vessels correlated closely between TSE MRI and CT (r(2)=.85) with a bias toward overestimation with MRI (mean 22.4 ± 4.3mm and 20.9 ± 3.7 mm, p<.01). CONCLUSION: This novel 3D respiratory gated TSE MR technique provides a feasible method to reduce metallic artifact and improve visualization of stented segments and surrounding anatomic structures without exposure to radiation.