Daniel Margolis

PI-RADS Prostate Imaging – Reporting and Data System: 2015, Version 2

The Prostate Imaging - Reporting and Data System Version 2 (PI-RADS™ v2) is the product of an international collaboration of the American College of Radiology (ACR), European Society of Uroradiology (ESUR), and AdMetech Foundation. It is designed to promote global standardization and diminish variation in the acquisition, interpretation, and reporting of prostate multiparametric magnetic resonance imaging (mpMRI) examination, and it is based on the best available evidence and expert consensus opinion. It establishes minimum acceptable technical parameters for prostate mpMRI, simplifies and standardizes terminology and content of reports, and provides assessment categories that summarize levels of suspicion or risk of clinically significant prostate cancer that can be used to assist selection of patients for biopsies and management. It is intended to be used in routine clinical practice and also to facilitate data collection and outcome monitoring for research.

Frequent Detection of Pancreatic Lesions in Asymptomatic High-Risk Individuals

BACKGROUND & AIMS The risk of pancreatic cancer is increased in patients with a strong family history of pancreatic cancer or a predisposing germline mutation. Screening can detect curable, noninvasive pancreatic neoplasms, but the optimal imaging approach is not known. We determined the baseline prevalence and characteristics of pancreatic abnormalities using 3 imaging tests to screen asymptomatic, high-risk individuals (HRIs). METHODS We screened 225 asymptomatic adult HRIs at 5 academic US medical centers once, using computed tomography (CT), magnetic resonance imaging (MRI), and endoscopic ultrasonography (EUS). We compared results in a blinded, independent fashion. RESULTS Ninety-two of 216 HRIs (42%) were found to have at least 1 pancreatic mass (84 cystic, 3 solid) or a dilated pancreatic duct (n = 5) by any of the imaging modalities. Fifty-one of the 84 HRIs with a cyst (60.7%) had multiple lesions, typically small (mean, 0.55 cm; range, 2-39 mm), in multiple locations. The prevalence of pancreatic lesions increased with age; they were detected in 14% of subjects younger than 50 years old, 34% of subjects 50-59 years old, and 53% of subjects 60-69 years old (P < .0001). CT, MRI, and EUS detected a pancreatic abnormality in 11%, 33.3%, and 42.6% of the HRIs, respectively. Among these abnormalities, proven or suspected neoplasms were identified in 85 HRIs (82 intraductal papillary mucinous neoplasms and 3 pancreatic endocrine tumors). Three of 5 HRIs who underwent pancreatic resection had high-grade dysplasia in less than 3 cm intraductal papillary mucinous neoplasms and in multiple intraepithelial neoplasias. CONCLUSIONS Screening of asymptomatic HRIs frequently detects small pancreatic cysts, including curable, noninvasive high-grade neoplasms. EUS and MRI detect pancreatic lesions better than CT.

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.

Value of Targeted Prostate Biopsy Using Magnetic Resonance–Ultrasound Fusion in Men with Prior Negative Biopsy and Elevated Prostate-specific Antigen

BACKGROUND Conventional biopsy fails to detect the presence of some prostate cancers (PCas). Men with a prior negative biopsy but persistently elevated prostate-specific antigen (PSA) pose a diagnostic dilemma, as some harbor elusive cancer. OBJECTIVE To determine whether use of magnetic resonance-ultrasound (MR-US) fusion biopsy results in improved detection of PCa compared to repeat conventional biopsy. DESIGN, SETTING, AND PARTICIPANTS In a consecutive-case series, 105 subjects with prior negative biopsy and elevated PSA values underwent multiparametric magnetic resonance imaging (MRI) and fusion biopsy in an outpatient setting. INTERVENTION Suspicious areas on multiparametric MRI were delineated and graded by a radiologist; MR-US fusion biopsy was performed by a urologist using the Artemis device; targeted and systematic biopsies were obtained regardless of MRI result. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS Detection rates of all PCa and clinically significant PCa (Gleason ≥3+4 or Gleason 6 with maximal cancer core length ≥4 mm) were determined. The yield of targeted biopsy was compared to systematic biopsy. The ability of an MRI grading system to predict clinically significant cancer was investigated. Stepwise multivariate logistic regression analysis was performed to determine predictors of significant cancer on biopsy. RESULTS AND LIMITATIONS Fusion biopsy revealed PCa in 36 of 105 men (34%; 95% confidence interval [CI], 25-45). Seventy-two percent of men with PCa had clinically significant disease; 21 of 23 men (91%) with PCa on targeted biopsy had significant cancer compared to 15 of 28 (54%) with systematic biopsy. Degree of suspicion on MRI was the most powerful predictor of significant cancer on multivariate analysis. Twelve of 14 (86%) subjects with a highly suspicious MRI target were diagnosed with clinically significant cancer. CONCLUSIONS MR-US fusion biopsy provides improved detection of PCa in men with prior negative biopsies and elevated PSA values. Most cancers found were clinically significant.

Targeted Biopsy in the Detection of Prostate Cancer Using an Office Based Magnetic Resonance Ultrasound Fusion Device

PURPOSE Targeted biopsy of lesions identified on magnetic resonance imaging may enhance the detection of clinically relevant prostate cancers. We evaluated prostate cancer detection rates in 171 consecutive men using magnetic resonance ultrasound fusion prostate biopsy. MATERIALS AND METHODS Subjects underwent targeted biopsy for active surveillance (106) or persistently increased prostate specific antigen but negative prior conventional biopsy (65). Before biopsy, each man underwent multiparametric magnetic resonance imaging at 3.0 Tesla. Lesions on magnetic resonance imaging were outlined in 3 dimensions and assigned increasing cancer suspicion levels (image grade 1 to 5) by a uroradiologist. A biopsy tracking system was used to fuse the stored magnetic resonance imaging with real-time ultrasound, generating a 3-dimensional prostate model on the fly. Working from the 3-dimensional model, transrectal biopsy of target lesions and 12 systematic biopsies were performed with the patient under local anesthesia in the clinic. RESULTS A total of 171 subjects (median age 65 years) underwent targeted biopsy. At biopsy, median prostate specific antigen was 4.9 ng/ml and prostate volume was 48 cc. A targeted biopsy was 3 times more likely to identify cancer than a systematic biopsy (21% vs 7%). Prostate cancer was found in 53% of men, 38% of whom had Gleason grade 7 or greater cancer. Of the men with Gleason 7 or greater cancer 38% had disease detected only on targeted biopsies. Targeted biopsy findings correlated with level of suspicion on magnetic resonance imaging. Of 16 men 15 (94%) with an image grade 5 target (highest suspicion) had prostate cancer, including 7 with Gleason 7 or greater cancer. CONCLUSIONS Prostate lesions identified on magnetic resonance imaging can be accurately targeted using magnetic resonance ultrasound fusion biopsy by a urologist in clinic. Biopsy findings correlate with level of suspicion on magnetic resonance imaging.

Clinical application of a 3D ultrasound-guided prostate biopsy system

OBJECTIVES Prostate biopsy (Bx) has for 3 decades been performed in a systematic, but blind fashion using 2D ultrasound (US). Herein is described the initial clinical evaluation of a 3D Bx tracking and targeting device (Artemis; Eigen, Grass Valley, CA). Our main objective was to test accuracy of the new 3D method in men undergoing first and follow-up Bx to rule out prostate cancer (CaP). MATERIALS AND METHODS Patients in the study were men ages 35-87 years (66.1 ± 9.9), scheduled for Bx to rule out CaP, who entered into an IRB-approved protocol. A total of 218 subjects underwent conventional trans-rectal US (TRUS); the tracking system was then attached to the US probe; the prostate was scanned and a 3D reconstruction was created. All Bx sites were visualized in 3D and tracked electronically. In 11 men, a pilot study was conducted to test ability of the device to return a Bx to an original site. In 47 men, multi-parametric 3 Tesla MRI, incorporating T2-weighted images, dynamic contrast enhancement, and diffusion-weighted imaging, was performed in advance of the TRUS, allowing the stored MRI images to be fused with real-time US during biopsy. Lesions on MRI were delineated by a radiologist, assigned a grade of CaP suspicion, and fused into TRUS for biopsy targeting. RESULTS 3D Bx tracking was completed successfully in 180/218 patients, with a success rate approaching 95% among the last 50 men. Average time for Bx with the Artemis device was 15 minutes with an additional 5 minutes for MRI fusion and Bx targeting. In the tracking study, an ability to return to prior Bx sites (n=32) within 1.2 ± 1.1 mm SD was demonstrated and was independent of prostate volume or location of Bx site. In the MRI fusion study, when suspicious lesions were targeted, a 33% Bx-positivity rate was found compared with a 7% positivity rate for systematic, nontargeted Bx (19/57 cores vs. 9/124 cores, P=0.03). CONCLUSION Use of 3D tracking and image fusion has the potential to transform MRI into a clinical tool to aid biopsy and improve current methods for diagnosis and follow-up of CaP.

Synopsis of the PI-RADS v2 Guidelines for Multiparametric Prostate Magnetic Resonance Imaging and Recommendations for Use

Department of Radiology and Nuclear Medicine Radboudumc, Nijmegen, The Netherlands; Yale School of Medicine, New Haven, CT, USA; University of Cincinnati, Cincinnati, OH, USA; Harvard University, Boston, MA, USA; University Hospital of Bern, Bern, Switzerland; AdMeTech Foundation, Boston, MA, USA; g Paul Strickland Scanner Centre, Mount Vernon Hospital, Northwood, Middlesex, UK; University of California, Los Angeles, CA, USA; i Johns Hopkins University, Baltimore, MD, USA; University of Toronto, Sunnybrook Health Sciences Centre, Toronto, Canada; Rene Descartes University, Paris, France; National Institutes of Health, Bethesda, MD, USA

Multifocality and Prostate Cancer Detection by Multiparametric Magnetic Resonance Imaging: Correlation with Whole-mount Histopathology

BACKGROUND Multiparametric magnetic resonance imaging (mp-MRI) is increasingly used in prostate cancer (CaP). Understanding the limitations of tumor detection, particularly in multifocal disease, is important in its clinical application. OBJECTIVE To determine predictors of CaP detection by mp-MRI as confirmed by whole-mount histopathology. DESIGN, SETTING, AND PARTICIPANTS A retrospective study was performed of 122 consecutive men who underwent mp-MRI before radical prostatectomy at a single referral academic center. A genitourinary radiologist and pathologist collectively determined concordance. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The odds of tumor detection were calculated for clinical, MRI, and histopathologic variables using a multivariate logistic regression model. RESULTS AND LIMITATIONS The 122 patients had 283 unique histologically confirmed CaP tumor foci. Gleason score was 6 in 21 (17%), 7 in 88 (72%), and ≥8 in 13 (11%) patients. Of the 122 cases, 44 (36%) had solitary and 78 (64%) had multifocal tumors. Overall mp-MRI sensitivity for tumor detection was 47% (132/283), with increased sensitivity for larger (102/141 [72%] >1.0 cm), higher-grade (96/134 [72%] Gleason ≥7) tumors, and index tumors (98/122 [80%]). Index tumor status, size, and prostate weight were significant predictors of detection in a multivariate analysis, and multifocality did not adversely impact detection of index tumors. A prostatectomy population was necessary by design, which may limit the ability to generalize these results. CONCLUSIONS Sensitivity for tumor detection increased with tumor size and grade. Index tumor status and tumor size were the strongest predictors of tumor detection, regardless of tumor focality. Some 80% of index tumors were detected, but nonindex tumor detection, even of high-grade lesions, was poor. These findings have important implications for focal therapy. PATIENT SUMMARY We evaluated the ability of magnetic resonance imaging (MRI) to detect cancer in patients undergoing prostatectomy. We found that tumor size and grade were important predictors of tumor detection, and although cancer is often multifocal, MRI is often able to detect the worst focus of cancer.

Prostate cancer detection with magnetic resonance-ultrasound fusion biopsy: The role of systematic and targeted biopsies.

The current study was conducted to evaluate the performance of magnetic resonance (MR)‐ultrasound‐guided fusion biopsy in diagnosing clinically significant prostate cancer (csCaP).

Clear cell renal cell carcinoma: discrimination from other renal cell carcinoma subtypes and oncocytoma at multiphasic multidetector CT.

PURPOSE To determine whether enhancement at multiphasic multidetector computed tomography (CT) can help differentiate clear cell renal cell carcinoma (RCC) from oncocytoma, papillary RCC, and chromophobe RCC. MATERIALS AND METHODS With institutional review board approval for this HIPAA-compliant retrospective study, the pathology database was queried to derive a cohort of 298 cases of RCC and oncocytoma with preoperative multiphasic multidetector CT with as many as four phases (unenhanced, corticomedullary, nephrographic, and excretory). A total of 170 clear cell RCCs, 57 papillary RCCs, 49 oncocytomas, and 22 chromophobe RCCs were evaluated for multiphasic enhancement and compared by using t tests. Cutoff analysis was performed to determine optimal threshold levels to discriminate among the four groups. RESULTS Mean enhancement of clear cell RCCs and oncocytomas peaked in the corticomedullary phase; mean enhancement of papillary and chromophobe RCCs peaked in the nephrographic phase. Enhancement of clear cell RCCs was greater than that of oncocytomas in the corticomedullary (125 HU vs 106 HU, P = .045) and excretory (80 HU vs 67 HU, P = .034) phases. Enhancement of clear cell RCCs was greater than that of papillary RCCs in the corticomedullary (125 HU vs 54 HU, P < .001), nephrographic (103 HU vs 64 HU, P < .001), and excretory (80 HU vs 54 HU, P < .001) phases. Enhancement of clear cell RCCs was greater than that of chromophobe RCCs in the corticomedullary (125 HU vs 74 HU, P < .001) and excretory (80 HU vs 60 HU, P = .008) phases. Thresholding of enhancement helped to discriminate clear cell RCC from oncocytoma, papillary RCC, and chromophobe RCC with accuracies of 77% (83 of 108 cases), 85% (101 of 119 cases), and 84% (81 of 97 cases). CONCLUSION Enhancement at multiphasic multidetector CT, if prospectively validated, may assist in the discrimination of clear cell RCC from oncocytoma, papillary RCC, and chromophobe RCC.