In-bore MRI-guided Prostate Biopsy Research Articles

The role of the size and number of index lesion in the diagnosis of clinically significant prostate cancer in patients with PI-RADS 4 lesions who underwent in-bore MRI-guided prostate biopsy.

To evaluate the contribution of the size and number of the sampled lesions to the diagnosis of clinically significant prostate cancer (CSPC) in patients who had PI-RADS 4 lesions. In this retrospective study, a total of 159 patients who had PI-RADS 4 lesions and underwent In-bore MRI-Guided prostate biopsy were included. Patients with a lesion classified as Grade Group 2 and above were considered to have CSPC. Univariate and multivariate regression analyses were used to evaluate the factors affecting the diagnosis of prostate cancer (PCa) and CSPC. A great majority (86.8%) of the patients were biopsy-naïve. About three-fourths (71.7%) had PCa, and half (54.1%) had CSPC. When the patients were divided into three groups according to the index lesion size (< 5mm, 5-10mm, and > 10mm), the prevalence of PCa was 64.3, 67.5, and 82.4% and the prevalence of CSPC was 42.9, 51.2, and 64.7%, respectively. In multivariate analysis, age, index lesion size, prostate volume (< 50ml) and being biopsy-naïve were found significant for PCa, while age and prostate volume (< 50ml) were significant for CSPC. The number of lesions was found to be insignificant in predicting PCa and CSPC. While the size of PI-RADS 4 lesions was significant in predicting PCa, it had no significance in detecting CSPC.

Imaging of clinically silent rectoprostatic hematoma in MRI guided in-bore prostate biopsy

MR imaging provides awareness for rectoprostatic hematomas as a complication in prostate biopsy. We evaluated the frequency and size of clinically silent bleeding after in-bore MRI-guided prostate biopsy according to documentation in MRI. From 2007 until 2020 in-bore MRI-guided prostate biopsy was performed in 283 consecutive patients with suspected prostate cancer. Interventional image documentation was reviewed for rectoprostatic hematomas and rectal blood collections in this retrospective observational single-center study. Correlation to patient characteristics was analyzed using a multivariable logistic regression model. 283 consecutive patients with a mean age of 66 ± 8 years were included. We diagnosed bleeding complications in 41 (14.5%) of the patients. Significant rectoprostatic hematomas were found in 24 patients. Intra-rectal blood collections were observed in 16 patients and one patient showed bleeding in the urinary bladder. The volume of rectoprostatic hematomas was determined with a median of 7.5 ml (range 2–40 ml, IQR 11.25). We found no correlation between the presence of a rectoprostatic hematoma and malignant findings, patient position in biopsy, number of cores, age, prostate volume nor PSA density (p > 0.05). Rectoprostatic hematomas and rectal blood collections are rare complications after in-bore MR-guided prostate biopsy. MR imaging provides benefits not only for lesion detection in prostate biopsy but also for the control of bleeding complications, which can be overlooked in standard TRUS biopsy. Their significance in pain, erectile dysfunction, and urinary retention remains to be investigated.

The urologist\u2019s learning curve of \u201cin-bore\u201d magnetic resonance-guided prostate biopsy

BackgroundThe combination of multi-parametric MRI to locate and define suspected lesions together with their being targeted by an MRI-guided prostate biopsy has succeeded in increasing the detection rate of clinically significant disease and lowering the detection rate of non-significant prostate cancer. In this work we investigate the urologist’s learning curve of in-bore MRI-guided prostate biopsy which is considered to be a superior biopsy technique.Materials and methodsFollowing Helsinki approval by The Chaim Sheba Medical Center ethics committee in accordance with The Sheba Medical Center institutional guidelines (5366-28-SMC) we retrospectively reviewed 110 IB-MRGpBs performed from 6/2016 to 1/2019 in a single tertiary center. All patients had a prostate multi-parametric MRI finding of at least 1 target lesion (prostate imaging reporting and data system [PI-RADS] score ≥ 3). We analyzed biopsy duration and clinically significant prostate cancer detection of targeted sampling in 2 groups of 55 patients each, once by a urologist highly trained in IB-MRGpBs and again by a urologist untrained in IB-MRGpBs. These two parameters were compared according to operating urologist and chronologic order.ResultsThe patients’ median age was 68 years (interquartile range 62–72). The mean prostate-specific antigen level and prostate size were 8.6 ± 9.1 ng/d and 53 ± 27 cc, respectively. The mean number of target lesions was 1.47 ± 0.6. Baseline parameters did not differ significantly between the 2 urologists’ cohorts. Overall detection rates of clinically significant prostate cancer were 19%, 55%, and 69% for PI-RADS 3, 4 and 5, respectively. Clinically significant cancer detection rates did not differ significantly along the timeline or between the 2 urologists. The average duration of IB-MRGpB targeted sampling was 28 ± 15.8 min, correlating with the number of target lesions (p < 0.0001), and independent of the urologist’s expertise. Eighteen cases defined the cutoff for the procedure duration learning curve (p < 0.05).ConclusionsOur data suggest a very short learning curve for IB-MRGpB-targeted sampling duration, and that clinically significant cancer detection rates are not influenced by the learning curve of this technique.

In-bore MRI-guided prostate biopsy in a patient group with PI-RADS 4 and 5 targets: A single center experience

PurposeTo determine the diagnostic yield of magnetic resonance imaging (MRI) guided in-bore biopsy in patients with high likelihood multiparametric MRI (mpMRI) findings, regarding overall and clinically significant prostate cancer (csPCa) detection rates and concordance of biopsy and radical prostatectomy (RP) Gleason scores (GS). MethodsThis retrospective study consisted of 277 Prostate Imaging Reporting and Data System (PI-RADS) assessment category 4 and 5 targets in 246 patients (mean age, 65.7 years; median prostate specific antigen value, 7.75 ng/mL) who had undergone in-bore biopsy at our institution between 2012 and 2020. Eighty-one patients who underwent RP were eligible for the concordance analysis of biopsy and RP specimen GS. ResultsOverall PCa detection rates were 80.5 % per patient (198/246) and 78 % per target (216/277) and 83.5 % and 67.4 % in primary (biopsy naive) and secondary (at least one negative prior biopsy) settings. csPCa was found in 63 % overall, 66 % of patients (132/200) in the primary, and 50 % of patients (23/46) in the secondary biopsy settings (p < 0.001). The prostate cancer detection rate was 68 % and 92 % in PI-RADS 4 and 5, respectively (p < 0.001).In the radical prostatectomy subcohort, 27.2 % of patients were upgraded, 8.6 % of patients were downgraded from needle biopsy. Significant complications occurred in 1.2 % of patients. ConclusionsMRI-guided in-bore prostate biopsy has a high detection rate of csPCa in primary and secondary biopsy cohorts. Biopsy results were satisfactory in terms of the number of positive cores, cancer percentage in positive cores, and concordance of GS in needle biopsy and RP specimen.

Impact of the Number of Cores on the Prostate Cancer Detection Rate in Men Undergoing in-Bore Magnetic Resonance Imaging-Guided Targeted Biopsies.

To determine the incremental detection rate of clinically significant prostate cancer (csPCa) provided by sequential cores during in-bore magnetic resonance imaging (MRI)-guided prostate biopsies. Single-center, retrospective interpretation of prospectively acquired data in men without previous diagnosis of csPCa who underwent in-bore MRI-guided prostate biopsy between May 2017 and December 2019. Endpoints included detection of csPCa (grade group [GG] ≥ 2) and rate of GG upgrade provided by additional cores. Descriptive statistics presented as mean and standard deviation for the continuous variables, and frequency and percentage for the categorical variables. Four hundred and forty-three men with 747 lesions met eligibility criteria. Clinically significant prostate cancer was detected in 43.1% (322/747) of the biopsied lesions and GG 2 PCa or greater was identified by the first core in 78.3% (252/322) of them. On a per-core basis, cores 2, 3, 4, and 5 found new csPCa in 6% (42/744), 4% (26/719), 1% (2/137), and 0% (0/11) of the cases. Core biopsy 2, 3, 4, and 5 resulted in GG upgrade in 12% (91/744), 7% (49/719), 7% (9/137), and 0% (0/11) of the lesions, respectively. Each additional core was associated with a mean increase of 5 minutes in the duration of the biopsy. In men undergoing in-bore MRI-guided prostate biopsies, 3 targeted cores per lesion provide an optimal trade-off between detection of clinically significant tumors and biopsy duration.

In-Bore MRI-guided Prostate Biopsies in Patients with Prior Positive Transrectal US-guided Biopsy Results: Pathologic Outcomes and Predictors of Missed Cancers.

To evaluate the role of confirmatory in-bore MRI-guided biopsy in patients with low- or intermediate-risk disease diagnosed at prior transrectal US-guided biopsy and to evaluate the rate and predictors for missed cancers. A retrospective evaluation of 50 consecutive men who had previously undergone transrectal US-guided biopsy with positive results and who underwent subsequent in-bore MRI-guided biopsy at our university hospital (average time interval, 11 months) between 2012 and 2016 was performed. Ten men were excluded because of a history of treatment after transrectal US-guided biopsy. A total of 40 men (mean age, 63 years; range, 47-84 years) were included in this study. Multiparametric 3-T MRI (T2-weighted, diffusion-weighted, and dynamic contrast material-enhanced) and transrectal in-bore MRI-guided biopsy were performed. Cancer detection, disease-grade changes, and cancers missed at in-bore MRI-guided biopsy were evaluated. Descriptive statistics were used to report different rates. The Fisher exact test was used for categoric variables. The Mann-Whitney U test and independent Student t test were used for nonparametric and parametric data, respectively. The McNemar test was used for paired data. The overall cancer detection rate when using in-bore MRI-guided biopsy was 65% (26 of 40). In-bore MRI-guided biopsy detected 14 previously undiscovered cancerous lesions (clinically significant cancers [CSCs], 57.1% [eight of 14]). An overall disease upgrade by in-bore MRI-guided biopsy occurred in 40% (16 of 40) of cases (61.5% [16 of 26] of cases with positive results from in-bore MRI-guided biopsy). One case was downgraded from a Gleason score (GS) of 3 + 4 = 7 to a GS of 3 + 3 = 6. Out of 71 sextant biopsies with positive results detected by transrectal US-guided biopsy (from all 40 patients), 80% (57 of 71) were visible on MR images (in-bore MRI-guided biopsy results were positive in 52.6% [30 of 57]), and 20% (14 of 71) had no image correlates on MR images. In-bore MRI-guided biopsy upgraded 60% (18 of 30) and downgraded 3.3% (one of 30) of detected lesions. The false-negative rate was 35% (14.2% [two of 14] of patients had CSCs; GS ≥ 7), was higher in prostate volumes of greater than 40 mL, and was lower in the anterior gland location (P = .04 and .01, respectively). Performing confirmatory in-bore MRI-guided biopsy following positive transrectal US-guided biopsy resulted in a high disease-upgrade incidence with subsequently improved disease-risk stratification, particularly when considering patients for active surveillance or focal therapy. Supplemental material is available for this article. © RSNA, 2020See also the commentary by Weiss and Solomon in this issue.

4D perfusion CT of prostate cancer for image-guided radiotherapy planning: A proof of concept study

PurposeAdvanced forms of prostate cancer (PCa) radiotherapy with either external beam therapy or brachytherapy delivery techniques aim for a focal boost and thus require accurate lesion localization and lesion segmentation for subsequent treatment planning. This study prospectively evaluated dynamic contrast-enhanced computed tomography (DCE-CT) for the detection of prostate cancer lesions in the peripheral zone (PZ) using qualitative and quantitative image analysis compared to multiparametric magnet resonance imaging (mpMRI) of the prostate.MethodsWith local ethics committee approval, 14 patients (mean age, 67 years; range, 57–78 years; PSA, mean 8.1 ng/ml; range, 3.5–26.0) underwent DCE-CT, as well as mpMRI of the prostate, including standard T2, diffusion-weighted imaging (DWI), and DCE-MRI sequences followed by transrectal in-bore MRI-guided prostate biopsy. Maximum intensity projections (MIP) and DCE-CT perfusion parameters (CTP) were compared between healthy and malignant tissue. Two radiologists independently rated image quality and the tumor lesion delineation quality of PCa using a five-point ordinal scale. MIP and CTP were compared using visual grading characteristics (VGC) and receiver operating characteristics (ROC)/area under the curve (AUC) analysis.ResultsThe PCa detection rate ranged between 57 to 79% for the two readers for DCE-CT and was 92% for DCE-MRI. DCE-CT perfusion parameters in PCa tissue in the PZ were significantly different compared to regular prostate tissue and benign lesions. Image quality and lesion visibility were comparable between DCE-CT and DCE-MRI (VGC: AUC 0.612 and 0.651, p>0.05).ConclusionOur preliminary results suggest that it is feasible to use DCE-CT for identification and visualization, and subsequent segmentation for focal radiotherapy approaches to PCa.

In-Bore MRI-guided Prostate Biopsies: Retrospective Observational Study of Complementary Nontargeted Sampling of Normal-appearing Areas at Multiparametric MRI.

To investigate the pathologic outcomes of additional random biopsies from areas with no visible MR targets in the setting of targeted in-bore MRI-guided biopsy and to assess the negative predictive value (NPV) of areas with no visible MR targets stratified according to patients' different biopsy statuses. A retrospective analysis of patients who underwent in-bore MRI-guided biopsy with additional random biopsies in areas with no visible MR targets (Prostate Imaging-Reporting and Data System, version 2 category 1 or 2) was conducted in this study. Diagnostic scans and in-bore MRI-guided biopsy were performed with a 3-T MRI scanner. Areas with no visible MR targets were biopsied in a random fashion whenever a zone or side did not have a visible focal target. Clinically significant cancers (CSCs) were defined as a Gleason score of 7 or greater. NPVs were stratified based on patient's prior biopsy status. Descriptive analysis was performed. A total of 59 consecutive patients were included, with a median age of 65 years (interquartile range [IQR], 59-71 years). The median prostate-specific antigen level was 7 ng/mL (IQR, 4.9-10.8 ng/mL). Of the 59 patients, 16 (27.1%) were biopsy naive, 24 (40.7%) had prior negative transrectal US-guided biopsy findings, and 19 (32.2%) had prior positive transrectal US-guided biopsy findings. Forty-two (71.2%) biopsies revealed prostate cancer. A total of 112 areas with no visible MR targets were biopsied, of which 20 (17.9%) were cancers and 11 (9.8%) were CSCs. The NPV of areas with no visible MR targets was approximately 78% for all cancers and was 88.1% for CSCs. NPVs in biopsy-naive patients, patients with prior negative transrectal US-guided biopsy findings, and patients with prior positive transrectal US-guided biopsy findings were 62.5%, 83.3%, and 84.2%, respectively, for all cancers and 75.0%, 91.7%, and 94.7%, respectively, for CSCs. Areas with no visible MR targets in patients with MR-suspicious foci may still harbor CSCs that may significantly affect management plans. Additional biopsies from areas with no visible MR targets are warranted in this population.Keywords: Biopsy/Needle Aspiration, Interventional-Body, MR-Imaging, Prostate, Urinary© RSNA, 2019.

Open Source Platform for Transperineal In-Bore MRI-Guided Targeted Prostate Biopsy.

Accurate biopsy sampling of the suspected lesions is critical for the diagnosis and clinical management of prostate cancer. Transperineal in-bore MRI-guided prostate biopsy (tpMRgBx) is a targeted biopsy technique that was shown to be safe, efficient, and accurate. Our goal was to develop an open source software platform to support evaluation, refinement, and translation of this biopsy approach. We developed SliceTracker, a 3D Slicer extension to support tpMRgBx. We followed modular design of the implementation to enable customization of the interface and interchange of image segmentation and registration components to assess their effect on the processing time, precision, and accuracy of the biopsy needle placement. The platform and supporting documentation were developed to enable the use of software by an operator with minimal technical training to facilitate translation. Retrospective evaluation studied registration accuracy, effect of the prostate segmentation approach, and re-identification time of biopsy targets. Prospective evaluation focused on the total procedure time and biopsy targeting error (BTE). Evaluation utilized data from 73 retrospective and ten prospective tpMRgBx cases. Mean landmark registration error for retrospective evaluation was 1.88 ± 2.63 mm, and was not sensitive to the approach used for prostate gland segmentation. Prospectively, we observed target re-identification time of 4.60 ± 2.40 min and BTE of 2.40 ± 0.98 mm. SliceTracker is modular and extensible open source platform for supporting image processing aspects of the tpMRgBx procedure. It has been successfully utilized to support clinical research procedures at our site.

In-bore MRI-guided biopsy: can it optimize the need for periodic biopsies in prostate cancer patients undergoing active surveillance? A pilot test-retest reliability study.

To evaluate the test-retest reliability of repeated in-bore MRI-guided prostate biopsy (MRGB). 19 lesions in 7 patients who had consecutive MRGBs were retrospectively analysed. Five patients had 2 consecutive MRGBs and two patients had 3 consecutive MRGBs. Both multiparametric MRI and MRGBs were performed using a 3T MRI scanner. Pathology results were categorized into benign, suspicious and malignant. Consistency between first and subsequent biopsy results were analysed as well as the negative predictive value (NPV) for prostate cancer. 15 lesions (≈79%) had matching second biopsy and 4 (21%) had non-matching second biopsy. Lesions with both Prostate Imaging - Reporting and Data System(PIRADS) categories 1 and 4 were all benign and had matching pathology results. Lesions with non-matching results had PIRADS categories 2, 3 and 5. NPV for prostate cancer in first biopsy was 87.5%. Overall agreement was 78.9% and overall disagreement was 21.1%.κ = 0.55 denoting moderate agreement (p = 0.002). 10/19 lesions had a third biopsy session. 9/10 (90%) had matching pathology results across the three biopsy sessions and all matching lesions were benign. In-bore MRI-guided prostate biopsy may have a better reliability for repeat biopsies compared to TRUS biopsy. Final conclusion awaits a prospective analysis on a larger cohort of patients. Advances in knowledge: This pilot study showed that repeated prostate in-bore MRI-guided prostate biopsy may have better reliability compared to TRUS biopsy with a suggested high NPV.

Interreader Agreement of Prostate Imaging Reporting and Data System Version 2 Using an In-Bore MRI-Guided Prostate Biopsy Cohort: A Single Institution's Initial Experience.

The purpose of this study is to determine the interobserver agreement of the Prostate Imaging Reporting and Data System version 2 (PI-RADSv2) for diagnosing prostate cancer using in-bore MRI-guided prostate biopsy as the reference standard. Fifty-nine patients underwent in-bore MRI-guided prostate biopsy between January 21, 2010, and August 21, 2013, and underwent diagnostic multiparametric MRI 6 months or less before biopsy. A single index lesion per patient was selected after retrospective review of MR images. Three fellowship-trained abdominal radiologists (with 1-11 years' experience) blinded to clinical information interpreted all studies according to PI-RADSv2. Interobserver agreement was assessed using Cohen kappa statistics. Thirty-eight lesions were in the peripheral zone and 21 were in the transition zone. Cancer was diagnosed in 26 patients (44%). Overall PI-RADS scores were higher for all biopsy-positive lesions (mean ± SD, 3.9 ± 1.1) than for biopsy-negative lesions (3.1 ± 1.0; p < 0.0001) and for clinically significant lesions (4.2 ± 1.0) than for clinically insignificant lesions (3.1 ± 1.0; p < 0.0001). Overall suspicion score interobserver agreement was moderate (κ = 0.45). There was moderate interobserver agreement among overall PI-RADS scores in the peripheral zone (κ = 0.46) and fair agreement in the transition zone (κ = 0.36). PI-RADSv2 scores were higher in the biopsy-positive group. PI-RADSv2 showed moderate interobserver agreement among abdominal radiologists with no prior experience using the scoring system.

Open-Source Platform for Prostate Motion Tracking During in-Bore Targeted MRI-Guided Biopsy.

Accurate sampling of cancer suspicious locations is critical in targeted prostate biopsy, but can be complicated by the motion of the prostate. We present an open-source software for intra-procedural tracking of the prostate and biopsy targets using deformable image registration. The software is implemented in 3D Slicer and is intended for clinical users. We evaluated accuracy, computation time and sensitivity to initialization, and compared implementations that use different versions of the Insight Segmentation Toolkit (ITK). Our retrospective evaluation used data from 25 in-bore MRI-guided prostate biopsy cases (343 registrations total). Prostate Dice similarity coefficient improved on average by 0.17 (p < 0.0001, range 0.02-0.48). Registration was not sensitive to operator variability. Computation time decreased significantly for the implementation using the latest version of ITK. In conclusion, we presented a fully functional open-source tool that is ready for prospective evaluation during clinical MRI-guided prostate biopsy interventions.

33 Detection of clinically significant prostate cancer by in-bore MRI-guided prostate biopsy

33 Detection of clinically significant prostate cancer by in-bore MRI-guided prostate biopsy

MRI-guided biopsies and minimally invasive therapy for prostate cancer.

Recent advances in multiparametric magnetic resonance imaging (mp-MRI) have led to a paradigm shift in the diagnosis and management of prostate cancer (PCa). Its sensitivity in detecting clinically significant cancer and the ability to localize the tumor within the prostate gland has opened up discussion on targeted diagnosis and therapy in PCa. Use of mp-MRI in conjunction with prostate-specific antigen followed by targeted biopsy allows for a better diagnostic pathway than transrectal ultrasound (TRUS) biopsy and improves the diagnosis of PCa. Improved detection of PCa by mp-MRI has also opened up opportunities for focal therapy within the organ while reducing the incidence of side-effects associated with the radical treatment methods for PCa. This review discusses the evidence and techniques for in-bore MRI-guided prostate biopsy and provides an update on the status of MRI-guided targeted focal therapy in PCa.

Magnetic Resonance Imaging-Guided Prostate Biopsy: How We Do It

Introduction: Prostate biopsy is typically performed under transrectal ultrasound (TRUS) guidance. However, even after multiple negative TRUS biopsies, the considerable risk of prostate cancer (PCa) remains due to undersampling.1,2 Magnetic resonance imaging (MRI) is increasingly used in clinical practice to guide prostate biopsies.3,4 In this video, we describe how we perform in-bore MRI-guided prostate biopsy and present an overview of this biopsy technique. The runtime of this video is 5:08 min. Materials and Methods: The biopsy procedure is illustrated by a clinical case of a 61-year-old male with a high clinical suspicion of PCa referred to our institution after six negative TRUS biopsy sessions. On preceding multiparametric MRI, a cancer suspicious region was identified at the left ventral transition zone. Targeted biopsy of this lesion was performed in a transrectal approach on a 3 T MR system using an MR-compatible biopsy device. In total, two biopsy cores were obtained from the suspicious region. Results and Conclusions: The illustrated case was performed in 26 minutes. On histopathology, a Gleason score 4+3 = 7 adenocarcinoma was present in, respectively, 8% and 50% of biopsy specimen volumes. In our institutional experience, an MRI-guided prostate biopsy in patients with previous negative TRUS biopsies achieved PCa detection rates in the order of 41%–59% using a median of three to four cores.5,6 Of detected cancers, 87%–93% was clinically significant. Median procedure time was 30–44 minutes. Urosepsis occurred in 0.4% of patients. Minor complications were observed in 1%–1.5% of patients. Overall, MRI-guided biopsy achieves high diagnostic performance, detecting more and predominantly clinically significant cancers using less cores than TRUS biopsy.7 Complication rates between both biopsy techniques are comparable.7 However, longer procedure times and limited general availability are limitations of the MRI-guided biopsy method. In conclusion, we feel that in-bore MRI-guided biopsy is an accurate and safe diagnostic tool to detect clinically significant PCa in patients with previous negative TRUS biopsies. C.O., J.B., D.Y.: Nothing to disclose; J.F.: Consultancy for Invivo, Schwerin, Germany. Runtime of video: 5 mins 8 secs

Recent advances in MRI-guided biopsy for prostate cancer detection

In-bore MRI-guided prostate biopsy is an accurate diagnostic technique for prostate cancer in males with clinical suspicion and previous negative transrectal ultrasound-guided prostate biopsies. In this article the current clinical applications of in-bore MRI-guided prostate biopsies are summarized.