3T Multiparametric Magnetic Resonance Imaging Research Articles

Can dynamic contrast-enhanced MR imaging based on radiomics improve the diagnostic efficiency of clinically significant prostate cancer?

Aims/Background Prostate cancer stands out as one of the most prevalent malignant tumours among males. The non-invasive identification of clinically significant prostate cancer via magnetic resonance imaging plays a critical role in circumventing unnecessary biopsies and determining suitable treatment strategies for patients. Our study aimed to evaluate the potential improvement in predictive accuracy for clinically significant prostate cancer by incorporating perfusion data obtained from dynamic contrast-enhanced magnetic resonance imaging acquisition protocols into multiparametric magnetic resonance imaging parameters. Methods Radiomics extracted from perfusion parameters (Ktrans, Kep, Ve) of dynamic contrast-enhanced magnetic resonance imaging were analysed in patients suspected of prostate cancer who underwent 3T multiparametric magnetic resonance imaging between January 2017 and June 2023 in this retrospective study. The pathological findings obtained from biopsy or therapy were categorised into groups based on the Gleason sum score as either clinically significant prostate cancer (Gleason sum score > 7) or non-clinically significant prostate cancer (Gleason sum score ≤ 6). Diagnostic models were constructed using logistic regression analysis, incorporating prostate imaging reporting and data system V2.1 scores and clinical data, with or without radiomics extracted from dynamic contrast-enhanced. The area under curve (AUC) values were compared using the DeLong test. Results Overall, 214 men (clinically significant prostate cancer [n=78] and non-clinically significant prostate cancer [n=136]) were included. The clinical-prostate imaging reporting and data system model demonstrated an AUC of 0.89 (95% confidence interval: 0.84-0.95) in the training cohort and 0.91 (95% confidence interval: 0.84-0.98) in the test cohort. For the clinical-prostate imaging reporting and data system-radscore model, the AUC values were 0.97 (95% confidence interval: 0.95-0.99) for Ktrans, 0.98 (95% confidence interval: 0.96-1.00) for Ve, and 0.96 (95% confidence interval: 0.93-0.98) for Kep in the training cohort, and 0.97 (95% confidence interval: 0.94-1.00) for Ktrans, 0.95 (95% confidence interval: 0.91-1.00) for Ve, and 0.97 (95% confidence interval: 0.94-1.00) for Kep in the test cohort. Radiomics based on perfusion parameters exhibited good diagnostic performance in predicting clinically significant prostate cancer. The clinical-prostate imaging reporting and data system-radscore model demonstrated superior diagnostic capability compared to perfusion-based radiomics or clinical-prostate imaging reporting and data system models alone. Conclusion The application of radiomics, which involves extracting perfusion parameters from dynamic contrast-enhanced imaging, has the potential to enhance diagnostic accuracy for clinically significant prostate cancer.

3T multiparametric MRI’s accuracy in detecting prostate cancer using Prostate Imaging Reporting and Data System (PIRADS) version 2.1 with prostate biopsy as a reference

BackgroundMultiparametric magnetic resonance imaging (MRI) is valuable in detecting prostate cancer due to its high sensitivity to malignant lesions. It is commonly utilized to improve the identification of clinically significant cancers within the prostate. This study aimed to correlate the findings from 3T multiparametric MRI of the prostate using the updated Prostate Imaging Reporting and Data System version 2.1 (PIRADSv2.1) from 2019 with reference to prostate biopsy results. Additionally, PIRADSv2.1 was used to calculate the sensitivity, specificity, positive predictive value, and negative predictive value of the 3T multiparametric MRI of the prostate.Methods and materialsA retrospective study was conducted at a tertiary center, wherein we identified patients who underwent a prostate biopsy between June 2019 and June 2021 and had a corresponding MRI of the prostate performed at the same institution, evaluated with PIRADSv2.1 criteria.ResultsA total of 50 patients were eligible for final analysis. The prevalence of prostate cancer was 69% (95% confidence interval (CI) 54–81%). Receiver operating characteristic (ROC) curves were generated for 3T multiparametric MRI of the prostate using PIRADSv2.1 to diagnose prostate cancer; the area under the ROC curve was 0.81 (95% CI 0.68–0.95, p < 0.001). The sensitivity, specificity, positive predictive value, and negative predictive value of the 3T multiparametric prostate MRI using PIRADSv2.1 were 74.0%, 87.0%, 92.9%, and 59.1%, respectively.ConclusionsPIRADSv2.1 exhibited good overall performance in the diagnosis of prostate cancer.

MP55-20 A NOVEL MACHINE LEARNING FRAMEWORK FOR AUTOMATED DETECTION OF PROSTATE CANCER LESIONS CONFIRMED ON MRI-INFORMED TARGET BIOPSY

MP55-20 A NOVEL MACHINE LEARNING FRAMEWORK FOR AUTOMATED DETECTION OF PROSTATE CANCER LESIONS CONFIRMED ON MRI-INFORMED TARGET BIOPSY

Role of magnetic resonance imaging for preoperative prediction of early biochemical failure in localized prostate cancer.

The purpose of our study was to assess preoperative clinical biological and Magnetic Resonance Imaging (MRI) predictive factors of early biochemical failure (BF), defined as persistence of significant post-operative plasmatic prostate specific antigen (PSA) level after radical prostatectomy (RP) in patients with localized prostate cancer (PCa). In a retrospective cohort study we included 142 patients from our university hospital with newly diagnosed PCa, who underwent 3T multiparametric MRI prior to RP. Only the MRI target lesions [Prostate Imaging Reporting and Data System (PIRADS) ≥3] with histological correspondence were considered significant. Clinical, biological, MRI and pathological preoperative data were studied. We performed univariate and multivariate logistic regression analysis to identify significant parameters associated with early BF. Early BF occurred in 14% of patients (20/142). Patients with BF had higher PSA level at diagnosis, Gleason score, number of positive biopsies, size of the largest positive biopsy and higher National Comprehensive Cancer Network (NCCN) risk score (P<0.001 for all). According to MRI, they also had higher T stage and a higher size of capsular contact (P<0.001 for all). In contrast, there was no difference concerning neither ADC value, perfusion profile and zonal location of the index lesion. In multivariate analysis, the best combination of predictive factors of early BF was the association of preoperative Gleason score ≥4+3 [odds ratio (OR) =6.8 (1.4-32.5); P=0.002] and T stage ≥3 on preoperative MRI [OR =17.4 (3.2-94.9); P<0.001] with an area under the curve (AUC) of 0.89 [99% confidence interval (CI): 0.77-1], a negative predictive value of 94% and a positive predictive value of 75%. Combination of simple preoperative biomarkers as Gleason score and T stage according to MRI accurately stratify the risk of early BF following RP. These results emphasize the pivotal role of preoperative MRI for the management of localized PCa.

Comparison Between Amide Proton Transfer Magnetic Resonance Imaging Using 3-Dimensional Acquisition and Diffusion-Weighted Imaging for Characterization of Prostate Cancer: A Preliminary Study.

This study aimed to compare diagnostic performance for tumor detection and for assessment of tumor aggressiveness in prostate cancer (PC) between amide proton transfer magnetic resonance imaging (MRI) with 3-dimensional acquisition (3DAPT) and diffusion-weighted imaging. The subjects were 23 patients with 27 pathologically proven PCs who underwent 3T multiparametric MRI. With reference to the pathology findings, 2 readers in consensus identified the location of PC on multiparametric MRI and measured APT signal intensity (APT SI [%]) and mean apparent diffusion coefficient (ADC) of the benign region and each PC lesion. The mean ADC showed a significant difference between benign regions and PC lesions (0.74 ± 0.15 vs 1.37 ± 0.21, P < 0.001), whereas APT SI did not ( P = 0.091). Lesion APT SI was significantly higher and lesion ADC was significantly lower in PCs with Gleason group (GG) ≥3 than in PCs with GG ≤2 (3.37 ± 1.30 vs 1.78 ± 0.67, P < 0.001, and 0.71 ± 0.18 vs 0.79 ± 0.10, P = 0.038, respectively). The APT SI was significantly higher in GG3 than in GG1, in GG3 than in GG2, and in GG4 than in GG2 ( P = 0.009, P = 0.001, and P = 0.006, respectively). The area under the curve for separating tumor lesions and benign regions was 0.601 for 3DAPT and 0.983 for ADC ( P < 0.001). The area under the curve for separating tumors with GG ≤2 from tumors with GG ≥3 was 0.912 for 3DAPT and 0.734 for ADC ( P = 0.172). In patients with PC, it might be preferable to use ADC to discriminate benign from malignant tissue and use APT SI for assessment of tumor aggressiveness.

Tumor Volume Predicts for Baseline Hypoxia Status in HPV Related Oropharyngeal Carcinomas (OPC) that Underwent Major Radiation De-escalation: The 30 Reduction in Oropharyngeal Cancer Trial

<h3>Purpose/Objective(s)</h3> The 30 ROC Trial utilizes functional imaging, specifically pre-treatment (Tx) and intra-Tx fluorine-18-labeled fluoromisonidazole positron emission tomography (18F-FMISO PET) to select appropriate human papillomavirus positive (HPV+) OPC patients for major de-escalation to 30 Gy. In this trial, patients also underwent pre-Tx and weekly multiparametric magnetic resonance imaging (MRI) scans to correlate with hypoxia status. The aim of the present study was to assess the value of MRI tumor volume to predict baseline hypoxia status in HPV+OPC patients who underwent major dose de-escalation. <h3>Materials/Methods</h3> A total (N = 158) patients with cT0-2,N1-2b (AJCC 7^th ed.) p16+ OPC were enrolled. All patients had pre-Tx 18F-FMISO PET scans to assess baseline hypoxia status, and only those with baseline hypoxia underwent a repeat intra-Tx scan. Pre-Tx and weekly intra-Tx MRI scans were acquired on technology company's 3T MRI scanner using a neurovascular phased array coil. Radiation oncologists delineated gross nodal disease as regions of interest on T₂w images. Tumor volume (cm³) was calculated in ITK SNAP for each patient using the segmentation software. All standard statistical analyses were performed on RStudio 2021.09.2. <h3>Results</h3> Of the 158 patients, N=95 patients had analyzable pre-Tx and weekly on-Tx MRI scans. Based on pre-Tx 18F-FMISO PET results, increased tumor volume was associated with baseline nodal hypoxia (N=69, median 18.55 cm³, range: 3.15- 60.62) compared to initially non-hypoxic tumors (N= 26, median 6.44 cm³, range: 0.48 – 47.74, p<0.001). After the intra-Tx 18F-FMISO PET result, patients were further stratified into converted negative (N= 57), persistently hypoxic (N=12), and never hypoxic (N=26). We found that the median pre-Tx nodal volume for the persistently hypoxic (median 17.75 cm³, range 5.54- 42.93, p=0.006) and converted negative (median 18.55 cm³, range 3.15 – 60.62, p<0.001) groups was significantly (P= <0.05) increased compared to the initially hypoxia negative patients (6.44 cm³, range 0.48 – 47.74). We performed further assessment of this pattern with intra-Tx MRIs (weeks 1-4) and found that this correlation of groups with baseline hypoxia (converted negative and persistently hypoxic) continued to exhibit larger nodal volume compared to the never hypoxic group. <h3>Conclusion</h3> Pre-Tx nodal volume on MRI correlates with pre-Tx hypoxia status where the larger the volume, the higher the likelihood of hypoxia. This correlation continued throughout radiation Tx as evidenced by the weekly MRI scans.

MP58-14 DISCORDANCE BETWEEN PROSTATE IMAGING REPORTING &amp; DATA SYSTEM SCORE AND TARGETED PROSTATE BIOPSY: AN OPPORTUNITY FOR QUALITY IMPROVEMENT

You have accessJournal of UrologyCME1 May 2022MP58-14 DISCORDANCE BETWEEN PROSTATE IMAGING REPORTING & DATA SYSTEM SCORE AND TARGETED PROSTATE BIOPSY: AN OPPORTUNITY FOR QUALITY IMPROVEMENT Rohith Arcot, Srinath Kotamarti, Madison Krischak, Zoe Michael, Isaac Alderete, Thomas Polascik, and Rajan Gupta Rohith ArcotRohith Arcot More articles by this author , Srinath KotamartiSrinath Kotamarti More articles by this author , Madison KrischakMadison Krischak More articles by this author , Zoe MichaelZoe Michael More articles by this author , Isaac AldereteIsaac Alderete More articles by this author , Thomas PolascikThomas Polascik More articles by this author , and Rajan GuptaRajan Gupta More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002641.14AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: We aim to estimate the positive predictive value (PPV) of Prostate Imaging Reporting & Data System (PI-RADS) score to identify any prostate cancer (PCa) and clinically significant prostate cancer (csPCa). Further, we sought to analyze cases of PI-RADS 5 discordance with biopsy pathology to develop a quality improvement protocol. METHODS: We retrospectively reviewed the Duke Prostate Cancer (PCa) registry for men who had a 3T multiparametric magnetic resonance imaging (mpMRI) of the prostate and underwent fusion biopsy by a single surgeon from 11/2015 – 3/2021. PI-RADS version 2-2.1 scores for all mpMRI lesions were compared to corresponding targeted biopsy results. The PPV of PI-RADS lesions was calculated for all PCa and csPCa, defined as Gleason Grade Group (GGG) > 2. The subset of discordant cases (PI-RADS 5 lesions with benign or GGG 1 pathology) were re-reviewed by a radiologist with expertise in prostate mpMRI to determine opportunities for quality improvement. RESULTS: A total of 524 targeted lesions were identified in 392 patients undergoing fusion biopsy of which a PI-RADS score of 5, 4, and 3 was assigned to 121 (23.1%), 310 (59.2%), and 90 (17.2%) lesions, respectively. The PPV of PI-RADS 5, 4, and 3 for all PCa and csPCa was 0.80, 0.55, 0.24, and 0.63, 0.33, and 0.09, respectively. Detection of csPCa was significantly higher for PI-RADS 5 lesions (62.8%) versus PI-RADS 4 lesions (33.2%) (p < 0.001). Still, PIRADS 5, discordant biopsy results were identified for 45 (37.2%) lesions. On mpMRI re-review, 18 (40.0%) lesions were considered “resolved” discordances as their suspicion was downgraded because either the lesion was > 1.5 cm alone without further abnormality (n=13), low signal central zone was mistaken for PCa (n=2), or the mpMRI was generally misread (n=3). The remaining 27 discordant cases had the level of suspicion confirmed on re-review and were classified as “unresolved.” After excluding “resolved” discordant cases, the PPV of PI-RADS 5 lesions improved to 0.74. CONCLUSIONS: Although PIRADS 5 lesions are considered high risk for csPCa, a diagnostic dilemma occurs when targeted biopsy returns benign or low grade cancer. In our cohort, a proportion of discordances were "resolved" by mpMRI re-review. Further work is needed to determine the value of re-biopsy in cases of “unresolved” discordance. We found re-review of PI-RADS 5 discordance events to be a source of potential quality improvement as the review of these cases allows for the identification of those who may benefit from re-biopsy versus close surveillance. Source of Funding: None © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e997 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Rohith Arcot More articles by this author Srinath Kotamarti More articles by this author Madison Krischak More articles by this author Zoe Michael More articles by this author Isaac Alderete More articles by this author Thomas Polascik More articles by this author Rajan Gupta More articles by this author Expand All Advertisement PDF DownloadLoading ...

MP11-03 PERFORMANCE OF 3T MULTIPARAMETRIC MRI FOR THE DETECTION OF SEMINAL VESICAL INVASION IN PATIENTS WITH PROSTATE CANCER

You have accessJournal of UrologyProstate Cancer: Staging (MP11)1 Sep 2021MP11-03 PERFORMANCE OF 3T MULTIPARAMETRIC MRI FOR THE DETECTION OF SEMINAL VESICAL INVASION IN PATIENTS WITH PROSTATE CANCER Sohrab Afshari Mirak, Anthony Sisk, Ely Felker, David Lu, Robert Reiter, and Steven Raman Sohrab Afshari MirakSohrab Afshari Mirak More articles by this author , Anthony SiskAnthony Sisk More articles by this author , Ely FelkerEly Felker More articles by this author , David LuDavid Lu More articles by this author , Robert ReiterRobert Reiter More articles by this author , and Steven RamanSteven Raman More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000001984.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Accurate Prostate Cancer (PCa) staging is critical in guiding a patient’s treatment decision and it could prevent both under treatment and over treatment. The emergence of focal therapy options has further increased the importance of accurate staging. Patients with pT3b disease (seminal vesical invasion (SVI)) exhibit a poorer prognosis due to increased treatment failure and tumor recurrence. In this study, we investigated the performance of 3T multiparametric Magnetic Resonance Imaging (3TmpMRI) for per-patient detection of SVI in patients with prostate cancer (PCa) with wholemount histopathology (WMHP) reference. METHODS: This IRB approved, HIPAA compliant observational study comprised of 647 consecutive men, who underwent 3TmpMRI prior to robotic radical prostatectomy. 3TmpMRI studies were performed with and without an endorectal coil (ERC) in 46.1% (270/586) and 53.9% (316/584) of cases, respectively. 3TmpMRI assessment for probability of SVI was evaluated on a Likert scale (1-5) and cases with score > 2 were considered suspicious for SVI. Per-patient performance of 3TmpMRI for the detection of SVI including sensitivity, specificity, PPV and NPV were evaluated in patients with at least one Region of Interest for PCa on MRI and the clinical (Age and PSA density (PSAD)), imaging (MRI assessment of SVI, ERC, index lesion's PIRADSv2 category, size, level, zone and average ADC) and biopsy (ratio of positive to total cores in systematic biopsy, maximum percentage of the core and highest Gleason Score (low=6 vs high >6)) parameters were compared between patients with and without SVI using bivariate analysis followed by multivariate analysis. RESULTS: SVI was present on WMHP in 8.9% (52/586) of the patients. Sensitivity, specificity, PPV and NPV were; 30.8% (16/52), 99.3% (530/534), 80% (16/20) and 93.6% (530/566), respectively. On multivariate regression analysis, older age (OR=1.11, p=0.001), PSAD (OR=26.3, p <0.001), 3TmpMRI SVI suspicion (OR=26, p<0.001) and lesion in the peripheral zone (PZ) (OR=16.6, p=0.008) and base (OR=2.4, p=0.023) were significantly associated with presence of SVI. The AUC for the ROC analysis of the final regression model was 0.84. CONCLUSIONS: 3TmpMRI has a high specificity, PPV and NPV and fair sensitivity for the detection of SVI. Patients with SVI tend to have older age, higher PSAD and higher likelihood of the index lesion in PZ and base of the prostate. Source of Funding: This work was supported by funds from the Integrated Diagnostics Program, Department of Radiological Sciences and Department of Pathology and Laboratory Medicine, David Geffen School of Medicine at UCLA © 2021 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 206Issue Supplement 3September 2021Page: e178-e178 Advertisement Copyright & Permissions© 2021 by American Urological Association Education and Research, Inc.MetricsAuthor Information Sohrab Afshari Mirak More articles by this author Anthony Sisk More articles by this author Ely Felker More articles by this author David Lu More articles by this author Robert Reiter More articles by this author Steven Raman More articles by this author Expand All Advertisement Loading ...

Tumor contact length of prostate cancer determined by a three‐dimensional method on multiparametric magnetic resonance imaging predicts extraprostatic extension and biochemical recurrence

To evaluate the clinical benefit of tumor contact length as a predictor of pathological extraprostatic extension and biochemical recurrence in patients undergoing prostatectomy. A total of 91 patients who underwent 3T multiparametric magnetic resonance imaging before prostatectomy from April 2014 to July 2019 were included. A total of 94 prostate cancer foci were analyzed retrospectively. We evaluated maximum tumor contact length, which was determined to be the maximum value in the three-dimensional directions, as a predictor of pathological extraprostatic extension and biochemical recurrence. A total of 19 lesions (20.2%) had positive pathological extraprostatic extension. Areas under the curves showed maximum tumor contact length to be a significantly better parameter to predict pathological extraprostatic extension than the Prostate Imaging Reporting and Data System (P=0.002), tumor maximal diameter (P=0.001), prostate-specific antigen (P=0.020), Gleason score (P<0.001), and clinical Tstage (P<0.001). Multivariate analysis showed maximum tumor contact length (P=0.003) to be an independent risk factor for predicting biochemical recurrence. We classified the patients using preoperative factors (prostate-specific antigen >10, Gleason score >3+4 and maximum tumor contact length >10mm) into three groups: (i) high-risk group (patients having all factors); (ii) intermediate-risk group (patients having two of three factors); and (iii) low-risk group (patients having only one or none of the factors). Kaplan-Meier curves showed that the high-risk group had significantly worse biochemical recurrence than the intermediate-risk group (P=0.042) and low-risk group (P<0.001). Our findings suggest that maximum tumor contact length is an independent predictor of pathological extraprostatic extension and biochemical recurrence. A risk stratification system using prostate-specific antigen, Gleason score and maximum tumor contact length might be useful for preoperative assessment of prostate cancer patients.

The diagnostic accuracy of multiparametric MRI for detection and localization of prostate cancer depends on the affected region.

ObjectivesTo determine the diagnostic accuracy of 3T multiparametric magnetic resonance imaging (mpMRI) for detecting and locating prostate cancer (PCa) on Dickinson's 27‐sector map, using histopathology specimens from radical prostatectomy (RP) as the reference standard.Patients and methodsThe authors studied a continuous series of 140 patients who underwent RP over three consecutive years. Prior to RP, all patients had mpMRI for detection and localization of PCa and further assessment by biopsy. To minimize the potential of disease progression, 25 patients were excluded because the interval between mpMRI and RP exceeded 6 months, which left 115 patients eligible for analysis. The mpMRI findings were reported using the Prostate Imaging‐Reporting and Data System (PI‐RADS) v2, considering PI‐RADS ≥ 3 to indicate PCa. The histopathology findings from RP specimens were graded using the Gleason scoring system, considering Gleason ≥ 6 to indicate PCa. The location of the tumors was mapped on Dickinson's 27‐sector map for both mpMRI and histopathology and compared by rigid sector‐by‐sector matching.ResultsThe cohort of 115 patients eligible for analysis was aged 66.5 ± 6.0 years at RP. Of the 3105 sectors analyzed, there were 412 true positives (13%), 28 false positives (1%), 68 false negatives (2%), and 2597 true negatives (84%). Across the 27 sectors of the prostate, mpMRI sensitivity ranged from 50% to 100% and specificity from 96% to 100%, while PPV ranged from 50% to 100%, and NPV from 91% to 100%. For the anterior prostate, mpMRI had a sensitivity of 80% (CI, 71%‐86%), specificity of 99% (CI, 99%‐100%), PPV of 91% (CI, 83%‐95%), and NPV of 99% (CI, 98%‐99%). For the posterior prostate, mpMRI had a sensitivity of 88% (CI, 84%‐91%), specificity of 98% (CI, 97%‐99%), PPV of 94% (CI, 92%‐96%), and NPV of 96% (CI, 94%‐97%). Overall, mpMRI had a sensitivity of 86%, specificity of 99%, PPV of 94%, and NPV of 97%.ConclusionsThe accuracy of mpMRI in detecting and locating prostate tumors depends on the affected region, but its high NPV across all sectors suggests that negative findings may not need corroboration by other techniques.

Prediction of clinically significant prostate cancer after negative prostate biopsy: The current value of microscopic findings

ObjectiveTo assess the current ability of atypical small acinar proliferation (ASAP), multifocal high-grade prostatic intraepithelial neoplasia (mHGPIN), HGPIN with atypia (PINATYP) and other non-malignant lesions to predict clinically significant prostate cancer (csPCa) in repeat prostate biopsies. MethodsThis retrospective study analyzed 377 repeat prostate biopsies, carried out between 2.014 and 2.017, and excluding those with previous PCa or 5-alpha reductase inhibitors treatment. ASAP, mHGPIN, PINATYP, prostatic atrophy, prostatic hyperplastic atrophy, proliferative inflammatory atrophy (PIA), chronic prostatitis, acute prostatitis, or granulomatous prostatitis, were prospectively reported after 12-core transrectal ultrasound (TRUS) systematic negative previous biopsies. 3T-multiparametric magnetic resonance imaging (mpMRI) was performed previous repeat biopsies. At least 2-core TRUS targeted biopsies of Prostate Imaging-Reporting and Data Systemv2 lesions ≥3, and/or 12-core TRUS systematic biopsy were performed in repeat prostate biopsies. The main outcome measurements were csPCa detection, which was defined when the International Society of Uro-Pathology group grade >1 and avoided biopsies. After logistic regression analysis the most efficient model was selected, nomogram was designed with internal validation, and clinical utility was analyzed. ResultsNormal benign tissue alone was present in less than 2% of previous negative biopsies. mHGPIN (39.7%), ASAP (4.3%) and PINATYP (3.7%) failed to predict csPCa risk in repeat biopsies. The finding of PIA (38.2%) associated with a decreased the risk of csPCa with an Odd ratio of 0.54 (95% confidence interval: 0.31–0.95), P= 0.031. The area under the curve, to predict csPCa, of mpMRI was 0.736, increasing up to 0.860 (95% confidence internal:0.82–0.90) when PSA density, age, digital rectal examination, and differential PSA between biopsies and PIA finding were integrated in a predictive model. At 6% threshold, more than 20% of repeat prostate biopsies were saved without missing csPCa. ConclusionCurrently, mHGPIN in negative prostate biopsy seems not able to predict the risk of future csPCa. The low incidence of ASAP and PINATYP, in our series, did not allow us to draw conclusions. PIA finding associated with a reduced risk of csPCa, and it could be integrated in a useful based-mpMRI predictive nomogram.

Efficacy of 3T Multiparametric MR Imaging followed by 3T in-Bore MR-Guided Biopsy for Detection of Clinically Significant Prostate Cancer Based on PIRADSv2.1 Score

PurposeTo evaluate the diagnostic yield of 3T in-Bore magnetic resonance-guided biopsy (3T IB-MRGB) for detection of clinically significant prostate cancer (csPCa), based on assessment using the Prostate Imaging Reporting and Data System version 2.1 (PIRADSv2.1). Materials and MethodsThis single-center study examined individuals who underwent 3T multiparametric prostate magnetic resonance (MR) imaging and subsequent 3T IB-MRGB. The final study cohort included 379 men (with 475 targets) divided into 3 subcohorts: biopsy-naïve men (n = 123), individuals with a history of negative trans-rectal-ultrasonography (TRUS) biopsy results (n = 106), and men with low-grade PCa under active surveillance (n = 150). csPCa was defined as having a Gleason score (GS) ≥3+4. Results3T IB-MRGB detected PCa and csPCa in 69.1% (262 of 379) and 50.3% (193 of 379) of patients, respectively. The PCa and csPCa detection rates per target were 64.2% (305 of 475) and 43.8% (208 of 475), respectively. The rate of urosepsis, treated with intravenous antibiotics, was 1% (4 patients). In TRUS biopsy negative results and biopsy-naïve subcohorts, csPCa was found in 36.8% (39 of 106) and 52.8% (65 of 123), respectively. In 50.7% (76 of 150) of the active surveillance subcohort, 3T IB-MRGB upgraded the GS assigned in prior TRUS biopsies. Positive predictive values of PIRADSv2.1 categories 3, 4, and 5 for csPCa detection were 24.8%, 44.4%, and 67.1%, respectively. Higher PIRADSv2.1 categories were significantly associated with PCa (odds ratio [OR], 3.97; 95% confidence interval [CI], 2.98–5.28) and csPCa (OR, 1.41; 95% CI, 1.03–1.94) detection. Of 137 PIRADSv2 category 3 lesions, 28 were downgraded to PIRADSv2.1 category 2, in which there were no occurrences of csPCa in histology. ConclusionsUse of 3T IB-MRGB resulted in detection of csPCa in 50.9% of individuals. 3T IB-MRGB has a high diagnostic yield in individuals with negative TRUS biopsy results and those under active surveillance. The PIRADSv2.1 category is a strong predictor of PCa and csPCa detection.

Combination of Peri-Tumoral and Intra-Tumoral Radiomic Features on Bi-Parametric MRI Accurately Stratifies Prostate Cancer Risk: A Multi-Site Study

Background: Prostate cancer (PCa) influences its surrounding habitat, which tends to manifest as different phenotypic appearances on magnetic resonance imaging (MRI). This region surrounding the PCa lesion, or the peri-tumoral region, may encode useful information that can complement intra-tumoral information to enable better risk stratification. Purpose: To evaluate the role of peri-tumoral radiomic features on bi-parametric MRI (T2-weighted and Diffusion-weighted) to distinguish PCa risk categories as defined by D’Amico Risk Classification System. Materials and Methods: We studied a retrospective, HIPAA-compliant, 4-institution cohort of 231 PCa patients (n = 301 lesions) who underwent 3T multi-parametric MRI prior to biopsy. PCa regions of interest (ROIs) were delineated on MRI by experienced radiologists following which peri-tumoral ROIs were defined. Radiomic features were extracted within the intra- and peri-tumoral ROIs. Radiomic features differentiating low-risk from: (1) high-risk (L-vs.-H), and (2) (intermediate- and high-risk (L-vs.-I + H)) lesions were identified. Using a multi-institutional training cohort of 151 lesions (D1, N = 116 patients), machine learning classifiers were trained using peri- and intra-tumoral features individually and in combination. The remaining 150 lesions (D2, N = 115 patients) were used for independent hold-out validation and were evaluated using Receiver Operating Characteristic (ROC) analysis and compared with PI-RADS v2 scores. Results: Validation on D2 using peri-tumoral radiomics alone resulted in areas under the ROC curve (AUCs) of 0.84 and 0.73 for the L-vs.-H and L-vs.-I + H classifications, respectively. The best combination of intra- and peri-tumoral features resulted in AUCs of 0.87 and 0.75 for the L-vs.-H and L-vs.-I + H classifications, respectively. This combination improved the risk stratification results by 3–6% compared to intra-tumoral features alone. Our radiomics-based model resulted in a 53% accuracy in differentiating L-vs.-H compared to PI-RADS v2 (48%), on the validation set. Conclusion: Our findings suggest that peri-tumoral radiomic features derived from prostate bi-parametric MRI add independent predictive value to intra-tumoral radiomic features for PCa risk assessment.

MRI-Guided Ultrafocal Salvage High-Dose-Rate Brachytherapy for Localized Radiorecurrent Prostate Cancer: Updated Results of 50 Patients

Most patients with local prostate cancer recurrence after radiation therapy undergo palliative androgen deprivation therapy because whole-gland salvage treatments have a high risk of severe toxicity. Focal treatment reduces this risk while offering a second opportunity for cure. We report updated outcomes of ultrafocal salvage high-dose-rate brachytherapy (HDR-BT). Prospectively collected data from the first 50 treated patients were analyzed. Disease status was assessed by 3T multiparametric magnetic resonance imaging (MRI), 18F-Choline or 68Ga-prostate-specific membrane antigen positron emission tomography/computed tomography, and systematic or tumor-targeted biopsies. Ultrafocal salvage HDR-BT (1 × 19 Gy) was performed by implanting the clinical target volume (CTV: gross tumor volume + 5 mm margin) under fused transrectal ultrasound/MRI guidance. Follow-up included toxicity grading (using Common Terminology Criteria for Adverse Events 4.0), quality of life assessment, and prostate-specific antigen (PSA) testing. Median follow-up was 31 months. Median CTV D95% was 18.8 Gy. We observed 2% grade 3 genitourinary toxicity, no grade 3 gastrointestinal toxicity, and 22% newly developed grade 3 erectile dysfunction. Five of 13 patients (38%) with self-reported pretreatment potency (International Index of Erectile Function >17) remained potent. Clinically relevant quality of life deterioration was reported for only 6 of 31 items and was not statistically significant. Biochemical failure (nadir + 2) occurred in 26 patients. Among intraprostatic recurrences, 73% were in field. After 2.5 years, biochemical disease-free survival was 51% (95% confidence interval, 37%-69%), metastases-free survival was 75% (64%-89%), androgen deprivation therapy-free survival was 90% (82%-99%), and overall survival was 98% (94%-100%). Presalvage PSA, CTV size, and stage ≥T3 were significantly associated with biochemical failure. Higher-risk patients (stage ≥T3, PSA ≥10, or PSA double time ≤9 months) had 25% biochemical disease-free survival at 2.5 years versus 71% for lower-risk patients. At this early stage, MRI-guided ultrafocal HDR-BT seems to be a safesalvage treatment option, with acceptable biochemical control in a well-selected group of patients and potential for effectively postponing androgen deprivation therapy.

Detectability of prostate cancer in different parts of the gland with 3-Tesla multiparametric magnetic resonance imaging: correlation with whole-mount histopathology.

We investigated whether the detectability of prostate cancer with 3-Tesla (3T) multiparametric magnetic resonance imaging (mpMRI) differs by tumor location. We identified 136 patients with prostate cancer who underwent 3-T mpMRI before prostatectomy at a single academic center. Two uroradiologists scored all MRIs with Prostate Imaging-Reporting and Data System version 2 (PI-RADS v2). A genitourinary pathologist mapped tumor foci from serial whole-mount radical prostatectomy sections. We assessed concordance of images with cancer sites. Tumor foci with Gleason score ≥ 3+4 or volume ≥0.5mL were considered significant. A total of 122 foci in 106 cases were identified with mpMRI. Twenty-four were PI-RADS 3, 52 were 4, and 46 were 5. A total of 274 tumor foci were identified with whole-mount pathology. The sensitivity stratified by location to detect significant cancer with a PI-RADS cutoff value of 3 was 56.0% overall, 50.0% in the peripheral zone (PZ), 71.2% in the transitional zone (TZ), 62.4% anterior, 49.5% posterior, 42.0% apical, 63.6% in the midgland, and 43.8% in the gland base. In multivariate analysis, tumor location was not a significant predictor of identification by mpMRI. Tumor volume, Gleason score, and index tumor status were significantly associated with identification by mpMRI. mpMRI detected the majority of high-grade and large cancers, but had low sensitivity in the PZ, posterior, and apex and base of the gland. The high prevalence of low-volume, low-Gleason score index tumors, as well as satellite tumors in those areas, accounted for the difference.

The Utility of Diffusion-Weighted Imaging and Perfusion Magnetic Resonance Imaging Parameters for Detecting Clinically Significant Prostate Cancer

IntroductionTo establish the diagnostic performance of the parameters obtained from dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and diffusion-weighted imaging at 3T in discriminating between non-clinically significant prostate cancers (ncsPCa, Gleason score [GS] < 7) and clinically significant prostate cancers (csPCa, GS ≥ 7) in the peripheral zone. Materials and MethodsTwenty-six male patients with peripheral zone prostate cancer (PCa) who had undergone 3T multiparametric magnetic resonance imaging (MRI) scan prior to biopsy were included in the study and evaluated retrospectively. The GS was obtained by both standard 12-core transrectal ultrasound guided biopsy and targeted MRI-US fusion biopsy and then confirmed by prostatectomy, if available. For each confirmed tumour focus, DCE-derived quantitative perfusion metrics (Ktrans, Kep, Ve, initial area under the curve [AUC]), the apparent diffusion coefficient (ADC) value, and normalized versions of quantitative metrics were measured and correlated with the GS. ResultsKtrans had the highest diagnostic accuracy value of 82% among the DCE-MRI parameters (AUC 0.90), and ADC had the strongest diagnostic accuracy value of 87% among the overall parameters (AUC 0.92). The combination of ADC and Ktrans have higher diagnostic performance with the area under the receiver operating characteristic curve being 0.98 (sensitivity 0.94; specificity 0.89; accuracy 0.92) compared to the individual evaluation of each parameter alone.The GS showed strong negative correlations with ADC (r = −0.72) and normalized ADC (r = −0.69) as well as a significant positive correlation with Ktrans (r = 0.69). ConclusionThe combination of Ktrans and ADC and their normalized versions may help differentiate between ncsPCa from csPCa in the peripheral zone.

Abstract 1397: Quantitative MR imaging measures predict intratumoral molecular heterogeneity in clear cell renal cell carcinoma

Abstract Clear cell renal cell carcinoma (ccRCC) is primarily driven by mutation in von Hippel-Lindau (VHL) leading to constitutive hypoxia inducible factors (HIFs) upregulation promoting angiogenesis. ccRCC is the most aggressive and common histological subtype of kidney cancer. It is characterized by high pathologic and molecular intra-tumor heterogeneity (ITH), a reflection of the genetic branched evolution during the tumor development. The overall molecular complexity in ccRCC may be underestimated with limited tissue samples in percutaneous biopsies. Non-invasive imaging methods that can provide quantitative spatial information on those varying features in the whole tumor may be a valuable tool for predicting tumor progression and therapy outcome. In this work we aim to understand the predictive value of quantitative Magnetic Resonance Imaging (MRI) measures of tumor vascularity as a noninvasive tool to identify molecular heterogeneity in ccRCC. In this IRB approved, prospective, HIPAA compliant study, 62 ccRCC patients underwent 3T multi-parametric MRI: T2-weighted (T2W), dynamic contrast-enhanced (DCE), and arterial spin labeled (ASL) MRI. All tumors were manually segmented with a region of interest (ROI) drawn on the central slice of the tumor. A grey-level co-occurrence matrix (GLCM) was constructed for each ROI and Haralick texture features were extracted. After surgery, 182 snap frozen samples from 49 tumors were subjected to RNA extraction, library preparation and mRNA sequencing using established protocols (Admerahealth, NJ). Spearman correlation coefficient between first- and second-order MRI statistics, including Haralick texture features, and gene expression levels were calculated. Gene ontology (GO) analysis was performed to identify the biological pathways associated with imaging features. Entropy, a measure of ITH, was correlated with standard deviation of normalized gene expression levels in multiple samples obtained from the same tumor. False discovery rate (FDR), q-values &amp;lt;0.05 were considered statistically significant. GO analysis of the top positively correlated genes with ASL-MRI and DCE-MRI measures of tumor perfusion indicated enrichment of immune system and cellular metabolic processes (q&amp;lt;0.05). ASL-MRI perfusion levels correlated positively with 81 HIF2 specific target genes (p&amp;lt;0.05). Gene set Enrichment Analysis (GSEA, Broad Institute, MA) indicated that correlated HIF2 target genes overlapped with key hallmark Molecular Signature database (MSigDB) gene sets, including G2M checkpoint, MTORC1 signaling, and glycolysis. Entropy of the DCE-MRI images correlated with heterogeneity in both metabolic processes, and expression of HIF1/2 target genes. Our study has set the initial framework for utilizing quantitative radiomics to assess the association of the imaging phenotype in ccRCC with specific molecular signatures. Citation Format: Durga Udayakumar, Ze Zhang, Durgesh Dwivedi, Yin Xi, Tao Wang, Ananth Madhuranthakam, Payal Kapur, Asghar Hajibeigi, Allison Joyce, Qurratulain Yousuf, Michael Fulkerson, Alberto Diaz de Leon, Matthew Lewis, Jeffrey Cadeddu, Aditya Bagrodia, Vitali Margulis, James Brugarolas, Ivan Pedrosa. Quantitative MR imaging measures predict intratumoral molecular heterogeneity in clear cell renal cell carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1397.

MRI-Guided Ultrafocal HDR Brachytherapy for Localized Prostate Cancer: Median 4-Year Results of a feasibility study

For the treatment of localized prostate cancer, focal therapy has the potential to cure with fewer side effects than traditional whole-gland treatments. We report an update on toxicity, quality of life (QoL), and tumor control in our magnetic resonance imaging (MRI)-guided ultrafocal high-dose-rate brachytherapy cohort. Disease status was evaluated by systematic biopsies and 3T multiparametric MRI. The brachytherapy implant procedure under fused transrectal ultrasound/MRI guidance was followed by a 1.5T MRI for contour adjustments and catheter position verification. A single dose of 19Gy was delivered to the tumor with a margin of 5mm. Genitourinary (GU) toxicity, gastrointestinal (GI) toxicity, and erectile dysfunction (ED) were graded with the Common Terminology Criteria for Adverse Events version 4.0. QoL was measured with RAND-36, European Organisation for Research and Treatment of Cancer QLQ-C30 and PR25. International Prostate Symptom Scores and International Index of Erectile Function scores were obtained. Prostate-specific antigen level was monitored, with biochemical recurrence defined as nadir + 2ng/mL (Phoenix). Thirty patients with National Comprehensive Cancer Network low- (13%) to intermediate-risk (87%) prostate cancer were treated between May 2013 and April 2016. Median follow-up was 4years. Median age was 71years (interquartile range, 68-73) and median initial prostate-specific antigen level was 7.3ng/mL (5.2-8.1). Maximum Gleason score was 4+3=7 (in 2 patients). All tumors were radiologic (MRI) stage T2. No grade >2 GU or >1 GI toxicity occurred. International Prostate Symptom Scores only deteriorated temporarily. Mild pretreatment ED deteriorated to moderate/severe ED in 50% of patients. Long-term clinically relevant QoL deterioration was seen in sexual activity and tiredness, whereas emotional and cognitive functioning improved. At 4years, biochemical disease-free survival was 70% (95% confidence interval, 52%-93%), metastases-free survival was 93% (85%-100%), and overall survival was 100%. Of intraprostatic recurrences, 7 of 9 were out of field. Ultrafocal high-dose-rate brachytherapy conveys minimal GU or GI toxicity and has a marginal effect on QoL. An early decline in erectile function was seen. Tumor control outcomes are poor (biochemical disease-free survival of 70% [52%-93%] at 4years), most likely as a result of poor patient selection.

The Introduction of 3T multiparametric magnetic resonance imaging of the prostate to a peripheral hospital – clinical utility and cost savings

The Introduction of 3T multiparametric magnetic resonance imaging of the prostate to a peripheral hospital – clinical utility and cost savings

The diagnostic value of PI-RADS V1 and V2 using multiparametric MRI in transition zone prostate clinical cancer.

The present study aimed to evaluate the efficacy of using the prostate imaging reporting and data system (PI-RADS) for the detection of prostate cancer (PCa) in the transitional zone (TZ) by 3T multiparametric magnetic resonance imaging (mpMRI), and to compare the diagnostic performance of PI-RADS V1 to V2 for the detection of PCa in the TZ. A total of 77 patients with suspicious lesions in the prostate TZ (83 cores) identified from mpMRI images acquired at 3T were scored per the PI-RADS system (V1 and V2) criteria. Magnetic resonance/transrectal ultrasound fusion-guided biopsy was performed in patients with at least one lesion classified as category ≥3 in the PI-RADS V1 assessment. The diagnostic performance of PI-RADS V1 for the detection of PCa in the TZ was compared with PI-RADS V2 by assessing the sensitivity, specificity and receiver operating characteristics. A total of 31 cases of PCa in the TZ and 46 cases of benign prostatic hyperplasia were confirmed by pathology, including 23 cases classified as Gleason score ≥7 and 54 cases of negative results and Gleason score 6. PI-RADS V2 exhibited a higher area under the curve (AUC, 0.888) compared with V1 (AUC, 0.869). The sensitivity of V2 (75.0%) was higher compared with that of V1 (68.8%), whereas the specificity of V2 (90.2%) was lower compared with that of V1 (96.1%) at PI-RADS scores of 11 and 4, respectively. The ESUR PI-RADS system may indicate the likelihood of PCa in suspicious lesions in the TZ on mpMRI. These results suggest that PI-RADS V2 performs better compared with V1 for the assessment of PCa in the TZ.