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Kang Z, Xu A, Wang L. Predictive role of T2WI and ADC-derived texture parameters in differentiating Gleason score 3 + 4 and 4 + 3 prostate cancer. JOURNAL OF X-RAY SCIENCE AND TECHNOLOGY 2021; 29:307-315. [PMID: 33522997 DOI: 10.3233/xst-200785] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
BACKGROUND Since Gleason score (GS) 4 + 3 prostate cancer (PCa) has a worse prognosis than GS 3 + 4 PCa, differentiating these two types of PCa is of clinical significance. OBJECTIVE To assess the predictive roles of using T2WI and ADC-derived image texture parameters in differentiating GS 3 + 4 from GS 4 + 3 PCa. METHODS Forty-eight PCa patients of GS 3 + 4 and 37 patients of GS 4 + 3 are retrieved and randomly divided into training (60%) and testing (40%) sets. Axial image showing the maximum tumor size is selected in the T2WI and ADC maps for further image texture feature analysis. Three hundred texture features are computed from each region of interest (ROI) using MaZda software. Feature reduction is implemented to obtain 30 optimal features, which are then used to generate the most discriminative features (MDF). Receiver operating characteristic (ROC) curve analysis is performed on MDF values in the training sets to achieve cutoff values for determining the correct rates of discrimination between two Gleason patterns in the testing sets. RESULTS ROC analysis on T2WI and ADC-derived MDF values in the training set (n = 51) results in a mean area under the curve (AUC) of 0.953±0.025 (with sensitivity 0.9274±0.0615 and specificity 0.897±0.069), and 0.985±0.013 (with sensitivity 0.9636±0.0446 and specificity 0.9726±0.0258), respectively. Using the corresponding MDF cutoffs, 95.3% (ranges from 76.5% to 100%) and 94.1% (ranged from 76.5% to 100%) of test cases (n = 34) are correctly discriminated using T2WI and ADC-derived MDF values, respectively. CONCLUSIONS The study demonstrates that using T2WI and ADC-derived image texture parameters has a potential predictive role in differentiating GS 3 + 4 and GS 4 + 3 PCa.
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Affiliation(s)
- Zhen Kang
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Technology and Science, Jiefang Avenue, Wuhan, China
| | - Anhui Xu
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Technology and Science, Jiefang Avenue, Wuhan, China
| | - Liang Wang
- Department of Radiology, Tongji Hospital, Tongji Medical College, Huazhong University of Technology and Science, Jiefang Avenue, Wuhan, China
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Schieda N, Lim CS, Zabihollahy F, Abreu-Gomez J, Krishna S, Woo S, Melkus G, Ukwatta E, Turkbey B. Quantitative Prostate MRI. J Magn Reson Imaging 2020; 53:1632-1645. [PMID: 32410356 DOI: 10.1002/jmri.27191] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 04/24/2020] [Accepted: 04/24/2020] [Indexed: 12/17/2022] Open
Abstract
Prostate MRI is reported in clinical practice using the Prostate Imaging and Data Reporting System (PI-RADS). PI-RADS aims to standardize, as much as possible, the acquisition, interpretation, reporting, and ultimately the performance of prostate MRI. PI-RADS relies upon mainly subjective analysis of MR imaging findings, with very few incorporated quantitative features. The shortcomings of PI-RADS are mainly: low-to-moderate interobserver agreement and modest accuracy for detection of clinically significant tumors in the transition zone. The use of a more quantitative analysis of prostate MR imaging findings is therefore of interest. Quantitative MR imaging features including: tumor size and volume, tumor length of capsular contact, tumor apparent diffusion coefficient (ADC) metrics, tumor T1 and T2 relaxation times, tumor shape, and texture analyses have all shown value for improving characterization of observations detected on prostate MRI and for differentiating between tumors by their pathological grade and stage. Quantitative analysis may therefore improve diagnostic accuracy for detection of cancer and could be a noninvasive means to predict patient prognosis and guide management. Since quantitative analysis of prostate MRI is less dependent on an individual users' assessment, it could also improve interobserver agreement. Semi- and fully automated analysis of quantitative (radiomic) MRI features using artificial neural networks represent the next step in quantitative prostate MRI and are now being actively studied. Validation, through high-quality multicenter studies assessing diagnostic accuracy for clinically significant prostate cancer detection, in the domain of quantitative prostate MRI is needed. This article reviews advances in quantitative prostate MRI, highlighting the strengths and limitations of existing and emerging techniques, as well as discussing opportunities and challenges for evaluation of prostate MRI in clinical practice when using quantitative assessment. LEVEL OF EVIDENCE: 5 TECHNICAL EFFICACY: Stage 2.
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Affiliation(s)
- Nicola Schieda
- Department of Medical Imaging, The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Christopher S Lim
- Department of Medical Imaging, Sunnybrook Health Sciences, Toronto, Ontario, Canada
| | | | - Jorge Abreu-Gomez
- Department of Medical Imaging, Sunnybrook Health Sciences, Toronto, Ontario, Canada
| | - Satheesh Krishna
- Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - Sungmin Woo
- Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York, USA
| | - Gerd Melkus
- Department of Medical Imaging, The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Eran Ukwatta
- Faculty of Engineering, Guelph University, Guelph, Ontario, Canada
| | - Baris Turkbey
- Molecular Imaging Program, National Cancer Institute NIH, Bethesda, Maryland, USA
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Comparing Prostate Imaging-Reporting and Data System Version 2 (PI-RADSv2) Category 1 and 2 Groups: Clinical Implication of Negative Multiparametric Magnetic Resonance Imaging. BIOMED RESEARCH INTERNATIONAL 2020; 2020:2819701. [PMID: 32337234 PMCID: PMC7154969 DOI: 10.1155/2020/2819701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 03/24/2020] [Indexed: 11/17/2022]
Abstract
Objectives To evaluate the clinicopathological differences between Prostate Imaging-Reporting and Data System (PI-RADS) version 2 (v2) category 1 and 2 groups. Materials and Methods. We retrospectively reviewed our two institutional clinical databases: (1) transrectal ultrasound (TRUS)/magnetic resonance imaging (MRI) fusion biopsy cohort (n = 706) and (2) radical prostatectomy (RP) cohort (n = 1403). Subsequently, we performed comparative analyses between PI-RADSv2 category 1 and 2 groups. Clinically significant prostate cancer (csPCa) was defined as the presence of Gleason score (GS) ≥ 3 + 4 in a single biopsy core, and adverse pathology (AP) was defined as high-grade (primary Gleason pattern 4 or any pattern 5) and/or non-organ-confined disease (pT3/N1). We also performed multivariate logistic regression analyses for AP. Results In the TRUS/MRI fusion biopsy cohort, no significant differences in detection rates of all cancer (18.2% vs. 29.0%, respectively, P = 0.730) or csPCa (9.1% vs. 9.9%, respectively, P = 0.692) were observed between PI-RADSv2 category 1 and 2 groups. There were no significant differences in pathologic outcomes including Gleason score (≥4 + 3, 21.2% vs. 29.9%, respectively, P = 0.420) or detection rate of AP (27.3% vs. 33.8%, respectively, P = 0.561) between the two groups in the RP cohort either. PI-RADSv2 category 1 or 2 had no significant association with AP, even in univariate analysis (P = 0.299). Conclusions PI-RADSv2 categories 1 and 2 had similar performance to predict clinicopathological outcomes. Consequently, these two categories may be unified into a single category. Negative mpMRI does not guarantee the absence of AP, as with csPCa.
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Roh AT, Fan RE, Sonn GA, Vasanawala SS, Ghanouni P, Loening AM. How Often is the Dynamic Contrast Enhanced Score Needed in PI-RADS Version 2? Curr Probl Diagn Radiol 2019; 49:173-176. [PMID: 31126664 DOI: 10.1067/j.cpradiol.2019.05.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/03/2019] [Accepted: 05/07/2019] [Indexed: 11/22/2022]
Abstract
BACKGROUND Prostate imaging reporting and data system version 2 (PI-RADS v2) relegates dynamic contrast enhanced (DCE) imaging to a minor role. We sought to determine how often DCE is used in PI-RADS v2 scoring. MATERIALS AND METHODS We retrospectively reviewed data from 388 patients who underwent prostate magnetic resonance imaging and subsequent biopsy from January 2016 through December 2017. In accordance with PI-RADS v2, DCE was deemed necessary if a peripheral-zone lesion had a diffusion-weighted imaging score of 3, or if a transition-zone lesion had a T2 score of 3 and diffusion-weighted imaging experienced technical failure. Receiver operating characteristic curve analysis assessed the accuracy of prostate-specific antigen density (PSAD) at different threshold values for differentiating lesions that would be equivocal with noncontrast technique. Accuracy of PSAD was compared to DCE using McNemar's test. RESULTS Sixty-nine lesions in 62 patients (16%) required DCE for PI-RADS scoring. Biopsy of 10 (14%) of these lesions showed clinically significant cancer (Gleason score ≥7). In the subgroup of patients with equivocal lesions, those with clinically significant cancer had significantly higher PSADs than those with clinically insignificant lesions (means of 0.18 and 0.13 ng/mL/mL, respectively; P= 0.038). In this subgroup, there was no statistical difference in accuracy in determining clinically significant cancer between a PSAD threshold value of 0.13 and DCE (P= 0.25). CONCLUSIONS Only 16% of our patients needed DCE to generate the PI-RADS version 2 score, raising the possibility of limiting the initial screening prostate MRI to a noncontrast exam. PSAD may also be used to further decrease the need for or to replace DCE altogether.
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Affiliation(s)
- Albert T Roh
- Department of Radiology, Stanford University, Stanford, CA
| | - Richard E Fan
- Department of Urology, Stanford University, Stanford, CA
| | - Geoffrey A Sonn
- Department of Radiology, Stanford University, Stanford, CA.; Department of Urology, Stanford University, Stanford, CA
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Song Z, Liao Z, Cui Y, Yang C. The relationship between homeobox B7 expression and the clinical characteristics of patient with prostate cancer. J Cell Biochem 2018; 120:6395-6401. [PMID: 30317675 DOI: 10.1002/jcb.27926] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Accepted: 09/25/2018] [Indexed: 12/14/2022]
Abstract
BACKGROUND The prognosis of patients with prostate cancer (PCa) remains poor. METHODS GSE16560, GSE32448, GSE79957, GSE17951, and TCGA-PRAD were reanalyzed to evaluate the expression of homeobox B7 (HOXB7) between PCa tissues and normal prostate tissues and to characterize the correlation between the expression of HOXB7 and the clinicopathological features of patients with PCa. Gene set enrichment analysis was conducted to investigate the mechanisms. RESULTS HOXB7 was upregulated in PCa tissues (P = 0.0005). Both the univariate and multivariate analyses demonstrated that the expression of HOXB7 was correlated with the Gleason score and TNM staging of patients with PCa. The Gleason score and TNM staging were higher in the HOXB7 high expression group. The overall survival (hazard ratio [HR] = 0.632; 95% confidence interval [CI]: 0.4773-0.8369; P = 0.0014) and progression-free survival (HR = 0.544; 95% CI: 0.3157-0.9373; P = 0.0283) favored patients with PCa in HOXB7 low expression group over those in HOXB7 high expression group. PCa samples in HOXB7 low expression group were enriched in gene sets associated with the epithelial mesenchymal transition, apical junction, angiogenesis, ultraviolet response, and hypoxia. CONCLUSIONS HOXB7 might be an independent prognostic factor of patients with PCa.
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Affiliation(s)
- Zhangxing Song
- Department of Urology, The National Hospital of Enshi Tujia and Miao Autonomous Prefecture, Enshi, Hubei Province, China
| | - Zhaolin Liao
- Department of Urology, The National Hospital of Enshi Tujia and Miao Autonomous Prefecture, Enshi, Hubei Province, China
| | - Yingdong Cui
- Department of Urology, The National Hospital of Enshi Tujia and Miao Autonomous Prefecture, Enshi, Hubei Province, China
| | - Chao Yang
- Department of Urology, The National Hospital of Enshi Tujia and Miao Autonomous Prefecture, Enshi, Hubei Province, China
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Glaser ZA, Porter KK, Thomas JV, Gordetsky JB, Rais-Bahrami S. MRI findings guiding selection of active surveillance for prostate cancer: a review of emerging evidence. Transl Androl Urol 2018; 7:S411-S419. [PMID: 30363494 PMCID: PMC6178314 DOI: 10.21037/tau.2018.03.21] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Active surveillance (AS) for prostate cancer (PCa) is generally considered to be a safe strategy for men with low-risk, localized disease. However, as many as 1 in 4 patients may be incorrectly classified as AS-eligible using traditional inclusion criteria. The use of multiparametric magnetic resonance imaging (mpMRI) may offer improved risk stratification in both the initial diagnostic and disease monitoring setting. We performed a review of recently published studies to evaluate the utility of this imaging modality for this clinical setting. An English literature search was conducted on PubMed for original investigations on localized PCa, AS, and magnetic resonance imaging. Our Boolean criteria included the following terms: PCa, AS, imaging, MRI, mpMRI, prospective, retrospective, and comparative. Our search excluded publication types such as comments, editorials, guidelines, reviews, or interviews. Our literature review identified 71 original investigations. Among these, 52 met our inclusion criteria. Evidence suggests mpMRI improves characterization of clinically significant prostate cancer (csPCa) foci, and the enhanced detection and risk-stratification afforded by this modality may keep men from being inappropriately placed on AS. Use of serial mpMRI may also permit longer intervals between confirmatory biopsies. Multiple studies demonstrate the benefit of MRI-targeted biopsies. The use of mpMRI of the prostate offers improved confidence in risk-stratification for men with clinically low-risk PCa considering AS. While on AS, serial mpMRI and MRI-targeted biopsy aid in the detection of aggressive disease transformation or foci of clinically-significant cancer undetected on prior biopsy sessions.
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Affiliation(s)
- Zachary A Glaser
- Department of Urology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Kristin K Porter
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - John V Thomas
- Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jennifer B Gordetsky
- Department of Urology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Pathology, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Soroush Rais-Bahrami
- Department of Urology, University of Alabama at Birmingham, Birmingham, AL, USA.,Department of Radiology, University of Alabama at Birmingham, Birmingham, AL, USA
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ADC Metrics From Multiparametric MRI: Histologic Downgrading of Gleason Score 9 or 10 Prostate Cancers Diagnosed at Nontargeted Transrectal Ultrasound–Guided Biopsy. AJR Am J Roentgenol 2018; 211:W158-W165. [DOI: 10.2214/ajr.17.18958] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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John S, Cooper S, Breau RH, Flood TA, Cagiannos I, Lavallee LT, Morash C, O'sullivan J, Schieda N. Multiparametric magnetic resonance imaging - Transrectal ultrasound-guided cognitive fusion biopsy of the prostate: Clinically significant cancer detection rates stratified by the Prostate Imaging and Data Reporting System version 2 assessment category. Can Urol Assoc J 2018; 12:401-406. [PMID: 29940139 DOI: 10.5489/cuaj.5254] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
INTRODUCTION We aimed to report the clinically significant prostate cancer (PCa) detection rate in men undergoing magnetic resonance imaging-transrectal ultrasound (MRI-TRUS)-cognitive fusion (CF) targeted biopsies stratified by the Prostate Imaging and Data Reporting System (PI-RADS) version 2 (v2) scores. METHODS With a quality assurance waiver from the IRB, we identified a cohort of men who underwent MRI-TRUS-CF and synchronous template biopsy from 2015-2017. MRI (PI-RADS v2 score, lesion size, lesion location [peripheral or transition zone (PZ/TZ)]), and CF-TRUS biopsy (operator experience, TRUS visibility, and number of biopsies) features were extracted. The primary outcome was diagnosis of clinically significant (Gleason score ≥3+4=7 or International Society of Urological Pathology (ISUP) grade group ≥2) PCa. RESULTS During the study period, 131 men (with 142 PIRADS v2 score ≥3 lesions) met inclusion criteria; 98 men had previously negative template biopsy and 33 were on active surveillance for previously detected low-grade PCa. In total, 41.9% (55/131) men had clinically significant PCa - 17.6% (23/131) detected on targeted biopsy only, 8.4% (11/131) on template biopsy only, and 16.0% (21/131) on both targeted and template biopsy. Clinically significant PCa detection stratified by PI-RADS v2 scores were: 11.1% (3/27) for score 3 (indeterminate), 42.9% (24/56) for score 4 (significant cancer likely), and 35.6% (21/59) for score 5 (significant cancer very likely). Clinically significant PCa detection rates in targeted biopsies were better among PZ (41.8% [33/79]) compared to TZ (23.8% [15/63]) lesions (p=0.025) in TRUS visible lesions (p=0.033) and in the most experienced radiologists (p=0.05), with no difference by lesion size or number of additional core biopsies performed (all p>0.05). CONCLUSIONS Cognitive fusion MRI-TRUS-guided targeted biopsy yielded substantially lower rates of clinically significant cancer in PI-RADS v2 score 4 and 5 lesions when compared to published results using in-bore MR-guided or automated MRI-TRUS fusion guidance systems. Cancer detection was worst for TZ lesions.
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Affiliation(s)
- Susan John
- The University of Ottawa, The Ottawa Hospital, Ottawa, ON, Canada
| | - Steven Cooper
- The University of Ottawa, The Ottawa Hospital, Ottawa, ON, Canada
| | - Rodney H Breau
- The University of Ottawa, The Ottawa Hospital, Ottawa, ON, Canada
| | - Trevor A Flood
- The University of Ottawa, The Ottawa Hospital, Ottawa, ON, Canada
| | - Ilias Cagiannos
- The University of Ottawa, The Ottawa Hospital, Ottawa, ON, Canada
| | - Luke T Lavallee
- The University of Ottawa, The Ottawa Hospital, Ottawa, ON, Canada
| | | | | | - Nicola Schieda
- The University of Ottawa, The Ottawa Hospital, Ottawa, ON, Canada
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Pesapane F, Patella F, Fumarola EM, Zanchetta E, Floridi C, Carrafiello G, Standaert C. The prostate cancer focal therapy. Gland Surg 2018; 7:89-102. [PMID: 29770305 PMCID: PMC5938267 DOI: 10.21037/gs.2017.11.08] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Accepted: 10/31/2017] [Indexed: 12/21/2022]
Abstract
Despite prostate cancer (PCa) is the leading form of non-cutaneous cancer in men, most patients with PCa die with disease rather than of the disease. Therefore, the risk of overtreatment should be considered by clinicians who have to distinguish between patients with high risk PCa (who would benefit from radical treatment) and patients who may be managed more conservatively, such as through active surveillance or emerging focal therapy (FT). The aim of FT is to eradicate clinically significant disease while protecting key genito-urinary structures and function from injury. While effectiveness studies comparing FT with conventional care options are still lacking, the rationale supporting FT relies on evidence-based advances such as the understanding of the index lesion's central role in the natural history of the PCa and the improvement of multiparametric magnetic resonance imaging (mpMRI) in the detection and risk stratification of PCa. In this literature review, we want to highlight the rationale for FT in PCa management and the current evidence on patient eligibility. Furthermore, we summarize the best imaging modalities to localize the target lesion, describe the current FT techniques in PCa, provide an update on their oncological outcomes and highlight trends for future research.
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Affiliation(s)
- Filippo Pesapane
- Postgraduation School in Radiodiagnostics, Università degli Studi di Milano, Milan, Italy
| | - Francesca Patella
- Postgraduation School in Radiodiagnostics, Università degli Studi di Milano, Milan, Italy
| | - Enrico Maria Fumarola
- Postgraduation School in Radiodiagnostics, Università degli Studi di Milano, Milan, Italy
| | - Edoardo Zanchetta
- Postgraduation School in Radiodiagnostics, Università degli Studi di Milano, Milan, Italy
| | - Chiara Floridi
- Azienda Ospedaliera Fatebenefratelli e Oftalmico, Milan, Italy
| | - Gianpaolo Carrafiello
- Department of Health Sciences, Diagnostic and Interventional Radiology, San Paolo Hospital, University of Milan, Milan, Italy
| | - Chloë Standaert
- Department of Radiology, Ghent University Hospital, Ghent, Belgium
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Galgano SJ, Glaser ZA, Porter KK, Rais-Bahrami S. Role of Prostate MRI in the Setting of Active Surveillance for Prostate Cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1096:49-67. [DOI: 10.1007/978-3-319-99286-0_3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Comparison of Prostate Imaging Reporting and Data System versions 1 and 2 for the Detection of Peripheral Zone Gleason Score 3 + 4 = 7 Cancers. AJR Am J Roentgenol 2017; 209:W365-W373. [PMID: 28981356 DOI: 10.2214/ajr.17.17964] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE The objective of our study was to compare Prostate Imaging Reporting and Data System version 1 (PI-RADSv1) and Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) for the detection of peripheral zone (PZ) Gleason score 3 + 4 = 7 cancers. MATERIALS AND METHODS Forty-seven consecutive patients with 52 PZ Gleason score 3 + 4 = 7 cancers that were 0.5 cm3 or larger underwent radical prostatectomy (RP) and 3-T MRI between 2012 and 2015. Two blinded radiologists (readers 1 and 2) retrospectively assigned PI-RADSv1 sequence (T2-weighted imaging, DWI, dynamic contrast-enhanced MRI [DCE-MRI]) and sum scores and PI-RADSv2 assessment categories. A third blinded radiologist (reader 3) measured apparent diffusion coefficient (ADC) ratio (ADC of tumor / ADC of normal PZ) using RP-MRI maps. Sensitivity, false-positive rate, and overall accuracy were compared using McNemar test. Pearson correlation was performed. RESULTS Using PI-RADSv1, reader 1 detected 86.5% (45/52) of the cancers and reader 2, 76.9% (40/52) of the cancers. Using PI-RADSv2, reader 1 detected 78.9% (41/52) and reader 2, 67.3% (35/52). Reader 1 detected 7.7% (4/52) and reader 2 detected 9.6% (5/52) more tumors using PI-RADSv1 due to T2-weighted imaging score ≥ 4 or DCE-MRI score ≥ 3. Sensitivity was higher for PI-RADSv1 (p = 0.01 and 0.03, readers 1 and 2). False-positive rates were higher with PI-RADSv1 than with PI-RADSv2 (1.8% vs 0.9% for reader 1; 3.6% vs 1.8% for reader 2) without significant differences in false-positive rate (p = 0.41 and 0.25) or overall accuracy (p = 0.06 and 0.23). PI-RADSv1 sum scores correlated strongly with PI-RADSv2 categories (B = 0.78-0.93, p < 0.0001). The mean ADC ratio was 0.61 ± 0.14 mm2/s with no difference between visible and nonvisible tumors (p = 0.06-0.5). Interobserver agreement was moderate for PI-RADSv2 (κ = 0.41) and ranged from slight to substantial for PI-RADSv1 (T2-weighted imaging, κ = 0.32; DWI, κ = 0.52; DCE-MRI, κ = 0.13). CONCLUSION There was no difference in overall detection of cancers comparing PI-RADSv1 and PI-RADSv2; however, PI-RADSv1 sequence scores on T2-weighted imaging and DCE-MRI detected approximately 10% more tumors that were otherwise underestimated on DWI and using PI-RADSv2 decision-tree rules.
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