Targeted Prostate Biopsy Research Articles

Prostate cancer segmentation from MRI by a multistream fusion encoder.

Targeted prostate biopsy guided by multiparametric magnetic resonance imaging (mpMRI) detects more clinically significant lesions than conventional systemic biopsy. Lesion segmentation is required for planning MRI-targeted biopsies. The requirement for integrating image features available in T2-weighted and diffusion-weighted images poses a challenge in prostate lesion segmentation frommpMRI. A flexible and efficient multistream fusion encoder is proposed in this work to facilitate the multiscale fusion of features from multiple imaging streams. A patch-based loss function is introduced to improve the accuracy in segmenting smalllesions. The proposed multistream encoder fuses features extracted in the three imaging streams at each layer of the network, thereby allowing improved feature maps to propagate downstream and benefit segmentation performance. The fusion is achieved through a spatial attention map generated by optimally weighting the contribution of the convolution outputs from each stream. This design provides flexibility for the network to highlight image modalities according to their relative influence on the segmentation performance. The encoder also performs multiscale integration by highlighting the input feature maps (low-level features) with the spatial attention maps generated from convolution outputs (high-level features). The Dice similarity coefficient (DSC), serving as a cost function, is less sensitive to incorrect segmentation for small lesions. We address this issue by introducing a patch-based loss function that provides an average of the DSCs obtained from local image patches. This local average DSC is equally sensitive to large and small lesions, as the patch-based DSCs associated with small and large lesions have equal weights in this average DSC. The framework was evaluated in 931 sets of images acquired in several clinical studies at two centers in Hong Kong and the United Kingdom. In particular, the training, validation, and test sets contain 615, 144, and 172 sets of images, respectively. The proposed framework outperformed single-stream networks and three recently proposed multistream networks, attaining F1 scores of 82.2 and 87.6% in the lesion and patient levels, respectively. The average inference time for an axial image was 11.8 ms. The accuracy and efficiency afforded by the proposed framework would accelerate the MRI interpretation workflow of MRI-targeted biopsy and focaltherapies.

PD38-06 WHAT IS THE IDEAL NUMBER OF CORES TO COLLECT PER REGION OF INTEREST DURING TARGETED PROSTATE BIOPSY?

You have accessJournal of UrologyCME1 Apr 2023PD38-06 WHAT IS THE IDEAL NUMBER OF CORES TO COLLECT PER REGION OF INTEREST DURING TARGETED PROSTATE BIOPSY? Casey Brodsky, Ji Qi, Kathryn Marchetti, and John Wei Casey BrodskyCasey Brodsky More articles by this author , Ji QiJi Qi More articles by this author , Kathryn MarchettiKathryn Marchetti More articles by this author , and John WeiJohn Wei More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003336.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Over the past decade, magnetic resonance imaging (MRI)-guided targeted prostate biopsy has been gaining favor over 12-core systematic biopsy for more accurate detection of clinically significant prostate cancers; however, no guidelines exist regarding the optimal number of biopsy cores that should be taken per region of interest (ROI) identified on MRI. An ideal number of cores balances maximizing cancer detection while minimizing patient discomfort, procedure time, and infection risk. In this project, we analyze the prostate cancer detection rate depending on core number for a large patient cohort. METHODS: Patients receiving targeted prostate cancer biopsy at the University of Michigan between January 2017 and June 2022 were identified. For each biopsy, 12 systematic cores were taken, as well as 4 cores per ROI. Statistical simulation was performed in SAS, using 500 iterations randomizing the order of cores taken, to assess cancer detection rate (CDR) and clinically significant cancer detection rate (CSCDR, defined as Gleason grade group ≥2) if 1, 2, or 3 versus 4 cores were taken per ROI. Chi-square tests were used to compare CDR and CSCDR between different scenarios. RESULTS: We identified 1022 patients, with 1095 total ROIs biopsied. Median age at time of biopsy was 65 (IQR 60-71), and median pre-biopsy PSA was 6.7 ng/mL (IQR 4.9-9.5). On systematic 12-core biopsy, CDR and CSCDR were 60% and 31%, respectively. On targeted biopsy considering all 4 cores, CDR and CSCDR were 59% and 39%, respectively. Combined biopsy considering systematic 12-core plus 4-core targeted biopsy showed CDR and CSCDR of 70% and 44%, respectively. Compared to taking 4 cores per ROI, taking fewer than 4 cores resulted in a decrease in both CDR and CSCDR, with statistically significant decreases seen for 1 and 2 versus 4 cores (Figure 1). This effect is mitigated when both targeted and systematic biopsy were combined. CONCLUSIONS: These analyses indicate that relative to 4 cores per ROI, cancer detection was inferior when only 1 or 2 cores are taken, but that 3 cores was not clinically nor statistically different than 4 cores. Source of Funding: N/A © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e995 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Casey Brodsky More articles by this author Ji Qi More articles by this author Kathryn Marchetti More articles by this author John Wei More articles by this author Expand All Advertisement PDF downloadLoading ...

V07-10 PROSTATE SPECIFIC MEMBRANE ANTIGEN (PSMA)-TARGETED PROSTATE BIOPSY

You have accessJournal of UrologyCME1 Apr 2023V07-10 PROSTATE SPECIFIC MEMBRANE ANTIGEN (PSMA)-TARGETED PROSTATE BIOPSY David Kuppermann, Jeremie Calais, and Leonard Marks David KuppermannDavid Kuppermann More articles by this author , Jeremie CalaisJeremie Calais More articles by this author , and Leonard MarksLeonard Marks More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003288.10AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: MRI-guided biopsy (MRGB) has emerged as the de facto standard for the best accuracy in diagnosis of prostate cancer (PCa). However, MRI is imperfect, and both falsely positive and falsely negative results have been observed. A new method has been developed for diagnosis of PCa by using a new way to image PCa anywhere in the body. In the present video we illustrate how PSMA-targeted prostate biopsy can complement conventional MRGB. METHODS: PSMA PET scanning employs a radiotracer labeled with gallium 68 (Ga68) or fluor 18 (F18). When injected the radiotracer binds to the extracellular part of the PSMA molecule which sits on the surface of PCa cells. The bound molecule then becomes internalized into the cytoplasm of PCa cells, where it accumulates allowing visualization by PET scanning. A CT scan is then performed and overlayed for anatomic localization. The result is a visual representation of PCa, wherever it may be in the body including within the prostate. RESULTS: PSMA PET/CT detects lesions suspicious for clinically significant PCa (csPCa). The degree of suspicion is based on the pattern of the PSMA PET signal. When focal, the level of suspicion increases. When diffuse and faint, the level of suspicion decreases. The PSMA PET signal intensity is also quantified using a metric called Standardized Uptake Value (SUV). The suspicious lesions identified on PSMA PET/CT can be contoured, transferred onto an ultrasound (US) image fusion device, and used as targets for biopsy. At our institution the Artemis device is used, but the procedure is also applicable to other fusion devices. The prostate is imaged using US, anesthetized, scanned, and a 3D representation of the prostate is created for targeting and tracking of biopsy data. Next the PET/CT image, with a contoured region of interest, is fused with real-time US images of the prostate. Biopsy samples targeted to the PSMA avid spot are obtained in and around the lesion. If not obtained previously, systematic samples may also be obtained at this time. The tissue cores are submitted individually for pathologic review. The workflow is identical to that used in MRI-US fusion procedures. At this time PSMA guided biopsies are limited to cases where MRI is suspected of being falsely negative or where MRI is contraindicated. At our institution we have performed 21 PSMA-targeted biopsies in men whose MRGBs were negative, but PSA density remained elevated, of which 14 (66.67%) showed csPCa (≥ GG2). CONCLUSIONS: PSMA scanning and PSMA-targeted biopsy have brought on a disruptive innovation in the world of prostate cancer. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e599 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information David Kuppermann More articles by this author Jeremie Calais More articles by this author Leonard Marks More articles by this author Expand All Advertisement PDF downloadLoading ...

Teleoperated and Automated Control of a Robotic Tool for Targeted Prostate Biopsy.

This work presents a robotic tool with bidirectional manipulation and control capabilities for targeted prostate biopsy interventions. Targeted prostate biopsy is an effective image-guided technique that results in detection of significant cancer with fewer cores and lower number of unnecessary biopsies compared to systematic biopsy. The robotic tool comprises of a compliant flexure section fabricated on a nitinol tube that enables bidirectional bending via actuation of two internal tendons, and a biopsy mechanism for extraction of tissue samples. The kinematic and static models of the compliant flexure section, as well as teleoperated and automated control of the robotic tool are presented and validated with experiments. It was shown that the controller can force the tip of the robotic tool to follow sinusoidal set-point positions with reasonable accuracy in air and inside a phantom tissue. Finally, the capability of the robotic tool to bend, reach targeted positions inside a phantom tissue, and extract a biopsy sample is evaluated.

A Multicenter, Randomized, Single-blind, 2-Arm Intervention Study Evaluating the Adverse Events and Quality of Life After Irreversible Electroporation for the Ablation of Localized Low-intermediate Risk Prostate Cancer. Reply.

No AccessJournal of UrologyReply to Letters to the Editor16 Mar 2023A Multicenter, Randomized, Single-blind, 2-Arm Intervention Study Evaluating the Adverse Events and Quality of Life After Irreversible Electroporation for the Ablation of Localized Low-intermediate Risk Prostate Cancer. Reply. Kai Zhang, Jeremy Teoh, Pilar Laguna, Chi-Fai Ng, and Jean de la Rosette Kai ZhangKai Zhang Department of Urology, Beijing United Family Hospital and Clinics, Beijing, China More articles by this author , Jeremy TeohJeremy Teoh S.H. Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China More articles by this author , Pilar LagunaPilar Laguna Department of Urology, Istanbul Medipol Mega University Hospital, Istanbul, Turkey More articles by this author , Chi-Fai NgChi-Fai Ng S.H. Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China More articles by this author , and Jean de la RosetteJean de la Rosette Department of Urology, Istanbul Medipol Mega University Hospital, Istanbul, Turkey More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003405AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack Citations ShareFacebookLinked InTwitterEmail "A Multicenter, Randomized, Single-blind, 2-Arm Intervention Study Evaluating the Adverse Events and Quality of Life After Irreversible Electroporation for the Ablation of Localized Low-intermediate Risk Prostate Cancer. Reply.." The Journal of Urology, Publish Ahead of Print, pp. – REFERENCES 1. . A multicenter, randomized, single-blind, 2-arm intervention study evaluating the adverse events and quality of life after irreversible electroporation for the ablation of localized low-intermediate risk prostate cancer. J Urol.2023; 209(2):347-353. Link, Google Scholar 2. . Focal therapy in prostate cancer-report from a consensus panel. J Endourol. 2010; 24(5):775-780. Crossref, Medline, Google Scholar 3. . Magnetic resonance imaging-targeted biopsy may enhance the diagnostic accuracy of significant prostate cancer detection compared to standard transrectal ultrasound-guided biopsy: a systematic review and meta-analysis. Eur Urol.2015; 68(3):438-450. Crossref, Medline, Google Scholar 4. . Multiparametric MRI for prostate cancer diagnosis: current status and future directions. Nat Rev Urol.2020; 17(1):41-61. Crossref, Medline, Google Scholar 5. . Transperineal multiparametric magnetic resonance imaging-ultrasound fusion targeted prostate biopsy combined with standard template improves prostate cancer detection. J Urol.2022; 207(1):86-94. Link, Google Scholar 6. . Schema and cancer detection rates for transperineal prostate biopsy templates: a review. Ther Adv Urol.2022; 14:175628722211050. Crossref, Google Scholar 7. . EAU—EANM—ESTRO—ESUR—ISUP—SIOG guidelines on prostate cancer—2020 update. Part 1: screening, diagnosis, and local treatment with curative intent. Eur Urol.2021; 79(2):243-262. Crossref, Medline, Google Scholar 8. . Effect of focal vs extended irreversible electroporation for the ablation of localized low- or intermediate-risk prostate cancer on early oncological control: a randomized clinical trial. JAMA Surg.2023. doi: 10.1001/jamasurg.2022.7516. Crossref, Google Scholar 9. . An updated systematic review on focal therapy in localized prostate cancer: what has changed over the past 5 years?Eur Urol.2022; 81(1):5-33. Crossref, Medline, Google Scholar 10. . Pair-matched patient-reported quality of life and early oncological control following focal irreversible electroporation versus robot-assisted radical prostatectomy. World J Urol.2018; 36(9):1383-1389. Crossref, Medline, Google Scholar Submitted February 26, 2023; accepted March 2, 2023; published 000. © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Kai Zhang Department of Urology, Beijing United Family Hospital and Clinics, Beijing, China More articles by this author Jeremy Teoh S.H. Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China More articles by this author Pilar Laguna Department of Urology, Istanbul Medipol Mega University Hospital, Istanbul, Turkey More articles by this author Chi-Fai Ng S.H. Ho Urology Centre, Department of Surgery, The Chinese University of Hong Kong, Hong Kong, China More articles by this author Jean de la Rosette Department of Urology, Istanbul Medipol Mega University Hospital, Istanbul, Turkey More articles by this author Expand All Submitted February 26, 2023; accepted March 2, 2023; published 000. Advertisement PDF downloadLoading ...

MRI to Ultrasound Cognitive Targeted Prostate Biopsy Provides all the Benefit of Ultrasound Fusion Without the Increased Resources

None.

Should a Targeted Prostate Biopsy be Performed for Every PI-RADS 3 Lesion Found on Multiparametric MRI of the Prostate?

Should a Targeted Prostate Biopsy be Performed for Every PI-RADS 3 Lesion Found on Multiparametric MRI of the Prostate?

Experience in Multiparametric magnetic resonance prior to targeted prostate biopsy: the tip of the iceberg for cancer detection?

Experience in Multiparametric magnetic resonance prior to targeted prostate biopsy: the tip of the iceberg for cancer detection?

Extracapsular extension of transitional zone prostate cancer miss-detected by multiparametric magnetic resonance imaging.

To demonstrate the importance of extracapsular extension (ECE) of transitional zone (TZ) prostate cancer (PCa), examine the causes of its missed detection by Mp-MRI, and develop a new predictive model by integrating multi-level clinical variables. This retrospective study included 304 patients who underwent laparoscopic radical prostatectomy after 12 + X needle transperineal transrectal ultrasound (TRUS)-MRI-guided targeted prostate biopsy from 2018 to 2021 in our center was performed. In this study, the incidence rates of ECE were similar in patients with MRI lesions in the peripheral zone (PZ) and TZ (P = 0.66). However, the missed detection rate was higher in patients with TZ lesions than in those with PZ lesions (P < 0.05). These missed detections result in a higher positive surgical margin rate (P < 0.05). In patients with TZ lesions, detected MP-MRI ECE may have grey areas: the longest diameters of the MRI lesions were 16.5-23.5mm; MRI lesion volumes were 0.63-2.51ml; MRI lesion volume ratios were 2.75-8.86%; PSA were 13.85-23.05ng/ml. LASSO regression was used to construct a clinical prediction model for predicting the risk of ECE in TZ lesions from the perspective of MRI and clinical features, including four variables: the longest diameter of MRI lesions, TZ pseudocapsule invasion, ISUP grading of biopsy pathology, and number of positive biopsy needles. Patients with MRI lesions in the TZ have the same incidence of ECE as those with lesions in the PZ, but a higher missed detection rate.

Limited relevance of the “very low risk” prostate cancer classification in the modern era: Results from a large institutional active surveillance cohort.

381 Background: Although the American Urological Association recently dropped the “very low risk” (VLR) category for prostate cancer (PCa), the National Comprehensive Cancer Network (NCCN) guidelines still maintain this stratum based on number of positive biopsy cores, tumor extent in each core, and PSA density. This subdivision may be outdated in the modern era in which targeted prostate biopsies are common practice. We identified the proportion of VLR patients at our institution to determine whether an alternative classification may be more appropriate for risk-stratification in the modern era. Methods: Participants were diagnosed from 2000-2019 with cT1-2N0/xM0/x PCa, PSA &lt;20ng/ml, biopsy Gleason grade group (GG) 1-2, and initially managed with AS. VLR PCa was defined as &lt;3 positive cores, ≤50% cancer per core, and PSA density &lt;0.15. UCSF-CAPRA score was calculated for each patient. The primary outcome was major upgrade (≥GG3) on subsequent biopsy. Multivariable Cox proportional hazards regression models were used to calculate associations between CAPRA score and risk of major upgrade, adjusting for age, genomic testing, and prostate MRI finding. Results: Of 1554 patients initially managed with AS, 364 (23%) met NCCN VLR criteria. 49 (3%), 781 (50%), 505 (33%), and 219 (14%) patients had CAPRA scores of 0, 1, 2, and 3, respectively. Proportion of patients deemed VLR decreased over time; among 84 patients initially managed with AS during or after 2018, only one patient (1%) met VLR criteria in 2018, while the stratification by CAPRA demonstrated that 21 (25%), 25 (30%), and 38 (45%) patients had CAPRA scores of 1, 2, and 3, respectively, over the same period. CAPRA score was significantly associated with major upgrade on biopsy on multivariable Cox proportional hazards regression modeling independent of age, genomic testing, and MRI finding (HR 1.46, 95%CI 1.22-1.74, p&lt;0.01). Conclusions: The relevance of VLR PCa in the modern targeted biopsy era has diminished, with no cases meeting VLR criteria in a large AS cohort after 2018. CAPRA score is an option for a more contemporary risk stratification tool for men on AS.

Does the percentage of Gleason 4 in patients with targeted prostate biopsies predict the percentage of Gleason 4 at final pathology results of radical prostatectomy specimen?

Does the percentage of Gleason 4 in patients with targeted prostate biopsies predict the percentage of Gleason 4 at final pathology results of radical prostatectomy specimen?

MRI/US fusion targeted prostate biopsies koelis®: Impact of operator experience on clinicaly significant prostate cancer detection

MRI/US fusion targeted prostate biopsies koelis®: Impact of operator experience on clinicaly significant prostate cancer detection

Significance of MRI-ultrasound fusion targeted prostate biopsy for non-index PI-RADS ≥3 lesions in combination with index lesion-targeted biopsy and systematic biopsy

Significance of MRI-ultrasound fusion targeted prostate biopsy for non-index PI-RADS ≥3 lesions in combination with index lesion-targeted biopsy and systematic biopsy

Time-course changes in multiparametric magnetic resonance imaging following focal cryotherapy for localized prostate cancer: Initial experience

PurposeTo evaluate the time-course changes of multiparametric MRI findings following focal cryotherapy for localized prostate cancer. MethodsSixteen patients who underwent focal cryotherapy as an initial curative treatment for localized prostate cancer during March 2017–April 2021 were included. Before the treatment, the patients underwent targeted prostate biopsy using MRI–transrectal ultrasound fusion. Overall, 64 MRIs were conducted after focal cryotherapy and the temporal post-treatment MR signal changes of the ablated area in T2WI, T1WI, DWI, and DCE-MRI were analyzed. ResultsTechnical success was achieved in all patients. The median follow-up period was 22 months. The initial post-treatment MRI revealed significant signal changes in the target lesions for all patients, including the disappearance of findings suggestive of cancer. At 3 months post-treatment, most lesions were hyperintense with a hypointense rim on T2WI, T1WI, and DWI (83.3 %). After 6 months, hyperintensity reduced, and after 17 months, all lesions showed hypointensity in these sequences. DCE-MRI of most patients showed loss of internal enhancement; however, one patient exhibited residual nodular enhancement in the ablated area at 3 months, which disappeared after 6 months. Peripheral enhancement was common at 3 months, disappearing after 23 months. Two patients showed biopsy-evidenced local recurrence. The recurrent lesions showed hypointensity on T2WI with diffusion restriction and early contrast enhancement in the ventral transition zone. ConclusionMRI findings of the ablated sites following focal cryotherapy for localized prostate cancer show dynamic signal changes, especially within the first 6 months.

Do cancer detection rates differ between transperineal and transrectal micro-ultrasound mpMRI-fusion-targeted prostate biopsies? A propensity score-matched study.

High-resolution micro-ultrasound (micro-US) is a novel precise imaging modality that allows targeted prostate biopsies and multiparametric magnet resonance imaging (mpMRI) fusion. Its high resolution relying on a 29 MHz transducer allows real-time visualisation of prostate cancer lesions; this might overcome the inaccuracy of conventional MRI-US fusion biopsy strategies. We compared cancer detection rates in patients who underwent transrectal (TR-B) versus transperineal (TP-B) MR-micro-US fusion biopsy. 1:2 propensity score matching was performed in 322 consecutive procedures: 56 TR-B and 266 TP-B. All prostate biopsies were performed using ExactVuTM micro-US system with mpMRI image fusion. Clinically significant disease was defined as grade group ≥2. The primary objective was to evaluate the detection of clinically significant disease according to access route. The secondary outcomes were to compare the respective detection rates of random and targeted biopsies stratified per access route and to evaluate micro-US for its potential added value. 47 men undergoing TR-B and 88 undergoing TP-B were matched for age, PSA, clinical stage, prostate volume, PIRADS score, number of mpMRI-visible lesions and indication to biopsy. The detection rates of clinically significant and of any prostate cancer did not differ between the two groups (45% TR-B vs 42% TP-B; p = 0.8, and 57% TR-B vs 59% TP-B; p = 0.9, respectively). Detection rates also did not differ significantly between random (p = 0.4) and targeted biopsies (p = 0.7) stratified per access route. Micro-US targeted biopsy detected 36 MRI-invisible lesions in 33 patients; 19% of these lesions were positive for clinically significant disease. Overall, micro-US targeted biopsies upgraded 2% of patients to clinically significant disease that would have been missed otherwise. MR-micro-US-fusion TR-B and TP-B have similar diagnostic yields in terms of detection rates of clinically significant prostate cancer. Micro-US targeted biopsy appears to have an additional diagnostic value over systematic and MRI-targeted biopsies.

Can we omit systematic biopsies in patients undergoing MRI fusion-targeted prostate biopsies?

Magnetic resonance imaging (MRI)-targeted prostate biopsy is the recommended investigation in men with suspicious lesion(s) on MRI. The role of concurrent systematic in addition to targeted biopsies is currently unclear. Using our prospectively maintained database, we identified men with at least one Prostate Imaging-Reporting and Data System (PI-RADS) ≥3 lesion who underwent targeted and/or systematic biopsies from May 2016 to May 2020. Clinically significant prostate cancer (csPCa) was defined as any Gleason grade group ≥2 cancer. Of 545 patients who underwent MRI fusion-targeted biopsy, 222 (40.7%) were biopsy naïve, 247 (45.3%) had previous prostate biopsy(s), and 76 (13.9%) had known prostate cancer undergoing active surveillance. Prostate cancer was more commonly found in biopsy-naïve men (63.5%) and those on active surveillance (68.4%) compared to those who had previous biopsies (35.2%; both P < 0.001). Systematic biopsies provided an incremental 10.4% detection of csPCa among biopsy-naïve patients, versus an incremental 2.4% among those who had prior negative biopsies. Multivariable regression found age (odds ratio [OR] = 1.03, P = 0.03), prostate-specific antigen (PSA) density ≥0.15 ng ml-2 (OR = 3.24, P < 0.001), prostate health index (PHI) ≥35 (OR = 2.43, P = 0.006), higher PI-RADS score (vs PI-RADS 3; OR = 4.59 for PI-RADS 4, and OR = 9.91 for PI-RADS 5; both P < 0.001) and target lesion volume-to-prostate volume ratio ≥0.10 (OR = 5.26, P = 0.013) were significantly associated with csPCa detection on targeted biopsy. In conclusion, for men undergoing MRI fusion-targeted prostate biopsies, systematic biopsies should not be omitted given its incremental value to targeted biopsies alone. The factors such as PSA density ≥0.15 ng ml-2, PHI ≥35, higher PI-RADS score, and target lesion volume-to-prostate volume ratio ≥0.10 can help identify men at higher risk of csPCa.

MR-Guided Targeted Prostate Biopsy from Radiologists' Perspective

The prostate cancer diagnosis has traditionally been based on a systematic biopsy method in which tissue samples are randomly obtained from the prostate 10-12 sites. However, there are concerns as the method can fail to diagnose all prostate cancers or lead to over-detection of clinically insignificant cancers. MRI-guided prostate targeted biopsy has been proposed to address these shortcomings. This method involves identifying suspicious lesions using MRI and performing targeted biopsies under ultrasound or MRI guidance. We review the methods of MRI-based targeted biopsy and discuss recent guidelines and trends in prostate cancer diagnosis.

Prostate cancer detection rate using MRI/ultrasound fusion-guided prostate biopsy in Siriraj Hospital

Objective: Systematic transrectal ultrasound (TRUS) guided biopsy has been considered a gold standard for prostate cancer diagnosis for many decades. The problem of this conventional method is the low detection rate especially in the case of repeat biopsy. This results from a limitation associated with ultrasound imaging inhibiting the visualization of cancerous lesions during the procedure. More recently, there has been increasing importance attributed to the use of multiparametric MRI for the identification of cancer inside the prostate gland. Targeted prostate biopsy, using multiparametric MRI/ultrasound (mpMRI/US) fusion-guided technology helps improve the detection of prostate cancer and has become a novel standard for tissue diagnosis. This study was conducted to investigate and report on the cancer detection rate of mpMRI/US fusion guided prostate biopsies at Siriraj Hospital. Materials and Methods: Data pertinent to patients who underwent mpMRI/US fusion guided biopsy at Siriraj Hospital between September 2017 and December 2019 was retrospectively reviewed. Results: A total of 499 men underwent mpMRI/US fusion guided biopsy, with the transperineal approach being used in the vast majority of cases (91.8%). Targeted biopsy provides a better cancer detection rate than systematic biopsy (55.3% vs 47.1%, p = 0.009). Combined targeted and systematic biopsies improved cancer detection rate compared to systematic biopsy alone (60.3% vs 47.1%, p &lt; 0.001). A subgroup analysis of men with positive biopsies showed that detection of clinically significant cancer (Gleason grade group ≥ 2) was no different between targeted and random biopsies (87.2% vs 80.8%, p = 0.11). The common complications from transperineal approach were urinary retention (5.4%) and hematuria (5.2%) while complications of infection were rare (0.2%). Conclusion: We found that targeted biopsy with mpMRI/US fusion guided technology provides a more effective option for prostate cancer diagnosis. A combination of targeted and systematic biopsy improve prostate cancer detection rate more effectively than systematic biopsy alone. The transperineal approach is a safe and effective technique with a rare incidence of infectious complications.

Role of the elastography strain ratio using transrectal ultrasonography in the diagnosis of prostate cancer and clinically significant prostate cancer

This study investigated the efficacy of the elastography strain ratio (ESR) as a predictor of prostate cancer (PCa) in targeted prostate biopsy. In total, 257 patients who underwent magnetic resonance imaging-targeted biopsy were enrolled. Before biopsy, we placed regions of interest (zone A and B) in the lesion and levator ani. The ESR was measured as zone A/zone B. Multivariate analyses were performed to predict PCa and clinically significant PCa. There were 206 (71.5%) positive cancer lesions. No difference in digit rectal examination findings was found between patients with and without PCa. For predicting clinically significant PCa, an ESR ≥ 6.8 was significantly higher in the PCa (+) group than in the PCa (−) group (p < 0.001). The area under the receiver operating characteristic curve (AUC) for the conventional variables (model 1) plus the ESR was 0.845, which was significantly higher than that for model 1 (p = 0.001). In prostate imaging reporting and data system score 3 lesions, an ESR ≥ 4.6 was a significant predictor of PCa (p = 0.002). The AUC in model 1 plus the ESR was 0.856, which was significantly higher than that in model 1 alone (p = 0.017). The ESR is useful for predicting clinically significant PCa.

Index lesion detection in multifocal prostate cancer: Simplified PI-RADS biparametric MRI vs PI-RADS v2.1 multiparametric MRI

ObjectiveTo assess the diagnostic performance of simplified PI-RADS (S-PI-RADS) with biparametric MRI (bpMRI) vs PI-RADS v2.1 with multiparametric MRI (mpMRI) in identifying lesion index (IL) in patients with multifocal prostate cancer (PCa)., The inter- and intra-observer variability was also determined with two readers. Materials and methodsRetrospective analysis of the prostate MRI of 59 patients with multifocal PCa (two or more tumors ascertained by TRUS/guided MRI targeted prostate biopsy). Two radiologists with experience in prostate MRI identified the IL in each patient according to S-PI-RADS-dedicated bpMRI. According to S-PI-RADS in multifocal intraprostatic lesions the IL was defined as the one with the greatest volume (when lesions with similar signal hypointensity on apparent diffusion coefficient (ADC) maps coexist), or as the lesion with marked hypointensity irrespective of volume (when lesions with moderate and marked signal hypointensity on ADC map coexist). Otherwise, according to PI-RADS v2.1 the IL is the one intraprostatic with the highest score.The agreement between the S-PI-RADS and PI-RADS v2.1 results and the histological data was expressed as a percentage of agreement or sensitivity (percentage of PCa or IL correctly identified on the total of PCas). The intra- and inter-observer agreement was evaluated with Cohen's kappa (k) coefficient. ResultsThe 133 lesions identified were compared with the biopsy results. Sensitivity in the detection of IL was 79.6–83% and 93.2–94.9% with the PI-RADS v2.1 and S-PI-RADS criteria, respectively, whereas the specificity was 83.8–86.5& and 94.6–96%. With both observers, the overall diagnostic accuracy was significantly higher using S-PI-RADS.Concerning the S-PI-RADS, the concordance between IL and tumor index (PCa with the highest Gleason score) was found in 56/59 patients (93%) both in the peripheral and transition zone. In the detection of the IL the agreement between the two readers was moderate (k = 0.701) for the PI-RADS v2.1 and good (k = 0.844) for the S-PI-RADS. A poor agreement between the two readers 0.38 (95% CI: 0.0653 to 0.693) and 0.41 (95% CI: 0.123 to 0.696) was revealed. ConclusionsIn patients with multifocal PCa, S-PI-RADS-based bpMRI showed significantly higher performance in IL detection and good inter-observer agreement.