Magnetic Resonance and Ultrasound Image Fusion Supported Transperineal Prostate Biopsy Using the Ginsburg Protocol: Technique, Learning Points, and Biopsy Results

Biopsy strategies in the era of mpMRI: a comprehensive review

BACKGROUND

Since its initial description the prostate biopsy technique for detection of prostate cancer (PCA) has constantly evolved. Multiparametric magnetic resonance imaging (mpMRI) has been proven to have a sensitivity exceeding 90% to detect the index lesion. This narrative review discusses the evidence around several biopsy strategies, especially in the context of patients that might be eligible for focal therapy.

METHOD

A non-systematic literature research was performed on February 15th 2024 using the Medical Literature Analysis and Retrieval System Online (Medline), Web of Science and Google Scholar.

RESULTS

The transrectal (TR) route is associated with an increased postoperative sepsis rate, even with adequate antibiotic prophylaxis. The transperineal (TP) route is now recommended by international guidelines, firstly for its decreased rate of urosepsis. Recent evidence shows a non-inferiority of TP compared to TR route, and even a higher detection rate of clinically significant PCA (csPCA) in the anterior and apical region, that are usually difficult to target using the TR route. Several targeting techniques (cognitive, software-fusion or in-bore) enhance our ability to provide an accurate risk assessment of prostate cancer aggressiveness and burden, while reducing the number of cores and reducing the number of clinically insignificant prostate cancer (ciPCA). While MRI-TB have proven their role, the role of systematic biopsies (SB) is still important because it detects 5-16% of csPCA that would have been missed by MRI-TB alone. The strategies of SB depend mainly on the route used (TR vs. TP) and the number of cores to be collected (10-12 cores vs. saturation biopsies vs. trans-perineal template mapping-biopsies or Ginsburg Protocol vs. regional biopsies).

CONCLUSION

Several biopsy strategies have been described and should be known when assessing patients for focal therapy. Because MRI systematically under evaluates the lesion size, systematic biopsies, and especially perilesional biopsies, can help to increase sensitivity at the cost of an increased number of cores.

Bi-parametric MRI-based quantification radiomics model for the noninvasive prediction of histopathology and biochemical recurrence after prostate cancer surgery: a multicenter study

RATIONALE AND OBJECTIVES

To develop and evaluate the performance of a noninvasive radiomics combined model based on preoperative bi-parametric MRI to assess biochemical recurrence (BCR) risk factors and to predict biochemical recurrence free survival in PCa patients.

MATERIALS AND METHODS

Pretreatment bp-MRI and clinicopathology data of 666 (discovery cohort, 545; test cohort, 121) PCa patients from four centers between January 2015 to March 2023 were retrospectively included. To predict BCR, extracapsular extension (ECE), pelvic lymph node metastasis (PLNM), and Gleason Grade group (GG), the pred-BCR, pred-ECE, pred-PLNM, and pred-GG models were developed, respectively. Subsequently, a logistic regression algorithm was used to combine one or more radiomics models and clinicopathology variables into radiomics-clinicopathology combined models (M1, M2) and radiomics-clinical combined model without pathology results (M3) for predicting BCR.

RESULTS

In the test cohort, the AUCs for the pred-BCR, pred-ECE, pred-PLNM, and pred-GG models were 0.841, 0.764, 0.896, and 0.698. Of the three combined models, M3 has the best prediction performance with an AUC of 0.884, M2 is the following with an AUC of 0.863, and M1 has the lowest performance with an AUC of 0.838 (95% CI 0.750-0.925) in the test cohort. Delong's test showed that the M3 was significantly higher (M1 vs. M3, p = 0.028; M2 vs. M3, p = 0.044).

CONCLUSION

The combined model developed in this study, which is not dependent on pathologic biopsies, can noninvasively predict postoperative histopathology and BCR after PCa, therefore may provide decision support for follow-up and treatment strategies for patients in the postoperative period.

Clinical utility of transperineal template-guided mapping prostate biopsy in a selection of patients under active surveillance and confirmation of patients with negative biopsy for prostate cancer

Purpose

We investigated the change to definitive treatment in patients under active surveillance (AS) and cancer diagnosis in non-cancerous patients for prostate cancer after confirmatory transperineal template-guided mapping biopsy (TTMB).

Materials and methods

A total of 336 patients who underwent TTMB between March 2017 and March 2023 were retrospectively reviewed, with 134 AS patients and 202 non-cancerous patients. All patients were routinely followed up via prostate-specific antigen (PSA) and multiparametric magnetic resonance imaging (mpMRI), and follow-up biopsy was performed when deemed clinically appropriate. Treatment changes in the AS and cancer detection in the non-cancerous group were analyzed. Descriptive statistics were used to analyze the retrospective data, and the Kaplan-Meier analysis was performed to indicate conversion to radical treatment in the AS group, as well as cancer detection in the previously benign non-cancerous group.

Results

One hundred thirty-four patients under the AS protocol were analyzed, of whom 110 (82.1%) maintained AS for 33 months. Nine patients (6.7%) had significant findings in mpMRI [Prostate Imaging-Reporting and Data System (PI-RADS) ≥3] and received radical treatment following target biopsy via transrectal ultrasonography. A total of 115 patients (83.3%) with insignificant findings in mpMRI (PI-RADS 1 or 2 lesions) were followed up via transrectal ultrasound-guided prostate biopsy (17.4%, N = 20), repeat TTMB (6.1%, N = 7), or no additional biopsy (76.5%, N = 88), and from each group, five (25.0%), two (28.5%), and eight (9.1%) patients converted to radical treatment. In the non-cancerous group, five patients (2.5%) were diagnosed with prostate cancer, with PI-RADS ≥ 3 findings via mpMRI, and were confirmed by target biopsy during a mean follow-up period of 25 months, subsequently receiving radical treatment.

Conclusions

TTMB is effective in selecting patients for AS treatment and confirming benign patients and can be used as an effective follow-up modality.

Do 5-Alpha Reductase Inhibitors Influence the Features of Suspicious Lesions on Magnetic Resonance Imaging and Targeted Biopsy Results for Prostate Cancer Diagnosis?

BACKGROUND

5-alpha reductase inhibitors (5-ARIs) change hormonal pathways and reduce prostate size. We evaluated the effects of 5-ARIs on prostatic multiparametric magnetic resonance imaging (mpMRI) suspicious findings and in the identification of prostate cancer using targeted biopsies.

METHODS

We conducted a retrospective study including 600 consecutive patients who, between 2017 and 2021, underwent combined transperineal fusion biopsies. Primary outcomes were Prostate Imaging Reporting and Data System version 2 (PIRADS v2) scores and the identification of clinically significant prostate cancer from suspicious lesions (targeted CSPC). Outcomes were compared between patients treated with 5-ARIs for a minimum of 6 months and the other patients.

RESULTS

Patients treated with 5-ARIs were older (p < 0.001) with higher rates of previous prostate biopsies (p = 0.004). PIRADS scores were 3, 4, and 5 in 15 (29%), 28 (54%), and 9 (17%) patients among the 5-ARI group and 130 (24%), 308 (56%), and 110 (20%) patients among the others, and the scores were not different between the groups (p = 0.69). The targeted CSPC identification rate among 5-ARI patients was 31%, not different compared to the non-5-ARI group (p = 1). Rates of targeted CSPC for each PIRADS score were not affected by 5-ARI treatment. The 5-ARI was not associated with neither PIRADS ≥ 4 score nor targeted CSPC on logistic regression analyses (OR = 0.76, 95% CI 0.4-1.4 and OR = 1.02, 95% CI 0.5-1.9, respectively).

CONCLUSIONS

5-ARI treatment is not associated with PIRADS score alterations or targeted biopsy results. Patients treated by 5-ARIs with suspicious lesions should not be addressed differently during the mpMRI-related diagnostic process.

Oncological Outcomes of Partial Gland Ablation Using High-Intensity Focused Ultrasound After Additional Confirmatory Transperineal Mapping Biopsy in Men with Prostate Cancer

BACKGROUND/OBJECTIVES

To evaluate whether additional confirmatory transperineal mapping biopsy (TPMB) in men with localized prostate cancer (PCa) alters the treatment plan and outcome of partial gland ablation (PGA) using high-intensity focused ultrasound (HIFU).

METHODS

We retrospectively reviewed data from 96 patients who underwent PGA using HIFU between January 2020 and June 2022. After multiparametric magnetic resonance imaging (mpMRI), all men underwent transrectal ultrasound (TRUS)-guided, cognitive-targeted biopsy and systematic biopsy. Men eligible for PGA using HIFU first underwent confirmatory TPMB. Any changes in the treatment plan after TPMB were analyzed. Follow-up TRUS-guided biopsy was performed 1 year post-operatively to evaluate oncological outcomes. Clinically significant PCa (csPCa) was defined as Gleason grade (GG) ≥ 2.

RESULTS

Among all subjects, the median age (IQR) was 65.0 (60.0-72.0) years and the prostate-specific antigen level was 5.20 (3.71-7.81) ng/mL. The results of both TRUS-guided biopsy and TPMB led to a change in the treatment plan (from unilateral to bilateral PGA) for 13 (13.5%) patients. The 1-year follow-up TRUS-guided biopsy identified PCa in 13 (13.5%) patients, and csPCa in 7 (7.3%) patients. The infield- and outfield-positive rates were 8.3% (8/96) and 3.1% (3/96), respectively, for any PCa, and 3.1% (3/96) and 2.1% (2/96), respectively, for csPCa.

CONCLUSIONS

Confirmatory TPMB results in better disease identification and localization, thereby affecting the treatment plan and improving oncological outcomes. Therefore, confirmatory TPMB should be considered to establish an appropriate strategy for patients with localized PCa eligible for PGA using HIFU.

Assessment of diagnostic value of unilateral systematic biopsy combined with targeted biopsy in detecting clinically significant prostate cancer

Objectives

This retrospective study assessed the diagnostic accuracy of targeted biopsy (TB) and unilateral systematic biopsy in detecting clinically significant prostate cancer (csPCa) in 222 men with single magnetic resonance imaging (MRI) lesions (Prostate Imaging Reporting and Data System [PI-RADS] ≥ 3).

Methods

Patients underwent multiparametric MRI and MRI/ultrasound fusion TB and 12-needle standard biopsy (SB) from September 2016 to June 2021. The study compared the diagnostic performance of TB + iSB (ipsilateral), TB + contralateral system biopsy (cSB) (contralateral), and TB alone for csPCa using the χ 2 test and analysis of variance.

Results

Among 126 patients with csPCa (ISUP ≥ 2), detection rates for TB + iSB, TB + cSB, and TB were 100, 98.90, and 100% for lesions, respectively. TB + iSB showed the highest sensitivity and negative predictive value. No significant differences in accuracy were found between TB + iSB and the gold standard for type 3 lesions (P = 1). For types 4-5, detection accuracy was comparable across methods (P = 0.314, P = 0.314, P = 0.153). TB had the highest positive needle count rate, with TB + iSB being second for type 3 lesions (4.08% vs 6.57%, P = 0.127).

Conclusion

TB + iSB improved csPCa detection rates and reduced biopsy numbers, making it a viable alternative to TB + SB for single MRI lesions.

MRI software and cognitive fusion biopsies in people with suspected prostate cancer: a systematic review, network meta-analysis and cost-effectiveness analysis

Background

Magnetic resonance imaging localises cancer in the prostate, allowing for a targeted biopsy with or without transrectal ultrasound-guided systematic biopsy. Targeted biopsy methods include cognitive fusion, where prostate lesions suspicious on magnetic resonance imaging are targeted visually during live ultrasound, and software fusion, where computer software overlays the magnetic resonance imaging image onto the ultrasound in real time. The effectiveness and cost-effectiveness of software fusion technologies compared with cognitive fusion biopsy are uncertain.

Objectives

To assess the clinical and cost-effectiveness of software fusion biopsy technologies in people with suspected localised and locally advanced prostate cancer. A systematic review was conducted to evaluate the diagnostic accuracy, clinical efficacy and practical implementation of nine software fusion devices compared to cognitive fusion biopsies, and with each other, in people with suspected prostate cancer. Comprehensive searches including MEDLINE, and Embase were conducted up to August 2022 to identify studies which compared software fusion and cognitive fusion biopsies in people with suspected prostate cancer. Risk of bias was assessed with quality assessment of diagnostic accuracy studies-comparative tool. A network meta-analysis comparing software and cognitive fusion with or without concomitant systematic biopsy, and systematic biopsy alone was conducted. Additional outcomes, including safety and usability, were synthesised narratively. A de novo decision model was developed to estimate the cost-effectiveness of targeted software fusion biopsy relative to cognitive fusion biopsy with or without concomitant systematic biopsy for prostate cancer identification in biopsy-naive people. Scenario analyses were undertaken to explore the robustness of the results to variation in the model data sources and alternative assumptions.

Results

Twenty-three studies (3773 patients with software fusion, 2154 cognitive fusion) were included, of which 13 informed the main meta-analyses. Evidence was available for seven of the nine fusion devices specified in the protocol and at high risk of bias. The meta-analyses show that patients undergoing software fusion biopsy may have: (1) a lower probability of being classified as not having cancer, (2) similar probability of being classified as having non-clinically significant cancer (International Society of Urological Pathology grade 1) and (3) higher probability of being classified at higher International Society of Urological Pathology grades, particularly International Society of Urological Pathology 2. Similar results were obtained when comparing between same biopsy methods where both were combined with systematic biopsy. Evidence was insufficient to conclude whether any individual devices were superior to cognitive fusion, or whether some software fusion technologies were superior to others. Uncertainty in the relative diagnostic accuracy of software fusion versus cognitive fusion reduce the strength of any statements on its cost-effectiveness. The economic analysis suggests incremental cost-effectiveness ratios for software fusion biopsy versus cognitive fusion are within the bounds of cost-effectiveness (£1826 and £5623 per additional quality-adjusted life-year with or with concomitant systematic biopsy, respectively), but this finding needs cautious interpretation.

Limitations

There was insufficient evidence to explore the impact of effect modifiers.

Conclusions

Software fusion biopsies may be associated with increased cancer detection in relation to cognitive fusion biopsies, but the evidence is at high risk of bias. Sufficiently powered, high-quality studies are required. Cost-effectiveness results should be interpreted with caution given the limitations of the diagnostic accuracy evidence.

Study registration

This trial is registered as PROSPERO CRD42022329259.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Evidence Synthesis programme (NIHR award ref: 135477) and is published in full in Health Technology Assessment; Vol. 28, No. 61. See the NIHR Funding and Awards website for further information.

Utility of transperineal template-guided mapping prostate biopsy in biopsy-naïve men with PI-RADS 1-2 on multiparametric magnetic resonance imaging

Objective

To analyze the outcomes of transperineal template-guided mapping biopsy (TTMB) in biopsy-naïve men with multiparametric magnetic resonance imaging (mpMRI) results of Prostate Imaging-Reporting and Data System (PI-RADS) 1-2.

Patients and methods

We retrospectively reviewed TTMB outcomes in biopsy naïve patients with PI-RADS 1-2 at a single center from August 2018 to May 2023. The patients' clinicopathologic data were reviewed, clinically significant prostate cancer (csPCa) detection rates were identified. We determined significant predictive factors and determined those optimal cutoff point using receiver operating characteristic (ROC) curves.

Results

255 biopsy naïve patients with PI-RADS 1-2 underwent TTMB. 72 (28.2%) were diagnosed with prostate cancer and 30 (11.8%) were diagnosed with csPCa. ROC curves were used to identify predictive factors for diagnosing csPCa. Age (area under ROC curve [AUC]: 0.74, 95% CI: 0.65-0.83, P < 0.001) and prostate specific antigen density (PSAD) (AUC: 0.63, 95% CI: 0.53-0.72, P = 0.025) were significant predictive factors, and the optimal cutoff points determined using the Youden index were 65 years and 0.15 ng/mL/mL, respectively.

Conclusion

Of biopsy-naïve patients classified as PI-RADS 1-2, 11.8% were diagnosed with csPCa, and we identified age and PSAD as significant predictive factors. Our study will help determine the biopsy method for patients with PI-RADS 1-2 without biopsy experience.

Are systematic prostate biopsy still necessary in biopsy naive men?

PURPOSE

Multiparametric MRI and the transperineal approach have become standard in the diagnostic pathway for suspected prostate cancer. Targeting of MRI lesions is performed at most centers, but the routine use of systematic cores is controversial. We aim to assess the value of obtaining systematic cores in patients undergoing cognitive fusion targeted double-freehand transperineal prostate biopsy.

MATERIALS AND METHODS

Patients who underwent a cognitive fusion, freehand TPB at a single tertiary urology service (Perth, Australia) between November 2020 and November 2021 were retrospectively reviewed. Patients were included if they were biopsy naive and had a clinical suspicion of prostate cancer, based on their mpMRI results. Both targeted and systematic cores were taken at the time of their biopsy.

RESULTS

One hundred forty patients suited the selection criteria. Clinically significant cancer was identified in 63% of patients. Of those that had clinically significant cancer, the target lesion identified 91% of the disease, missing 9% of patients whom the target biopsy detected non-clinically significant cancer but was identified in the systematic cores. Higher PI-RADS category patients were also found to be associated with an increasing likelihood of identifying clinically significant cancer within the target.

CONCLUSIONS

In patients with PI-RADS 3 and higher, the target biopsy can miss up to 9% of clinically significant cancer. Systematic cores can add value as they can also change management by identifying a high-risk disease where only intermediate cancer was identified in the target. A combination of targeted and systematic cores is still required to detect cancer.

Clinical and economic impact of the introduction of pre-biopsy MRI-based assessment on a large prostate cancer centre diagnostic population and activity: 10 years on

INTRODUCTION

Prostate mpMRI was introduced in 2011 as a secondary test and subsequently integrated into a prostate cancer (PCa) diagnostics unit representing a population of approximately 550,000 people. The following represents an audit of its step-wise introduction between 2 index years, 2009 and 2018, focusing on the activity, patient outcomes and economic benefits. PATIENTS AND METHODS: The 2 distinct years were selected for relying on a transrectal ultrasound biopsy pathway in 2009 to an mpMRI-based pathway in 2018. All referrals were retrospectively screened and compared for age, PSA levels, DRE findings, biopsy history, biopsy and mpMRI allocation data. Cost analysis was determined using local unit procedure costs.

RESULTS

Patients referred included 648 in 2009 and 714 in 2018. mpMRI seldomly informed decision to biopsy in 2009 (9.8%), while in 2018 it was performed in the pre-biopsy setting in 87.9% cases and enabled biopsy avoidance in 137 patients. In 2018, there was a 31.8% decrease in the number of biopsies in patients without previous PCa diagnosis, coupled with an increase in diagnostic rates of csPCa, from 28.6 to 49.0% (p < 0.0001) and a reduction in negative biopsy rates from 52.3 to 33.8%. mpMRI had a positive impact on the system with reduced patient morbidity and post-procedural complications. The estimated overall cost savings amount to approximately £75,000/year for PCa diagnosis and £11,000/year due to reduced complications.

CONCLUSION

Our evaluation shows the mpMRI-based pathway has improved early detection of csPCa and reduction of repeat biopsies, resulting in significant financial benefits for the local healthcare system.

Risk stratification of prostate cancer with MRI and prostate-specific antigen density-based tool for personalized decision making

OBJECTIVES

MRI is now established for initial prostate cancer diagnosis; however, there is no standardized pathway to avoid unnecessary biopsy in low-risk patients. Our study aimed to test previously proposed MRI-focussed and risk-adapted biopsy decision models on a real-world dataset.

METHODS

Single-centre retrospective study performed on 2055 biopsy naïve patients undergoing MRI. Diagnostic pathways included "biopsy all", "MRI-focussed" and two risk-based MRI-directed pathways. Risk thresholds were based on prostate-specific antigen (PSA) density as low (<0.10 ng mL-2), intermediate (0.10-0.15 ng mL-2), high (0.15-0.20 ng mL-2), or very high-risk (>0.20 ng mL-2). The outcome measures included rates of biopsy avoidance, detection of clinically significant prostate cancer (csPCa), missed csPCa, and overdiagnosis of insignificant prostate cancer (iPCa).

RESULTS

Overall cancer rate was 39.9% (819/2055), with csPCa (Grade-Group ≥2) detection of 30.3% (623/2055). In men with a negative MRI (Prostate Imaging-Reporting and Data System, PI-RADS 1-2), the risk of cancer was 1.2%, 2.6%, 9.0%, and 12.9% in the low, intermediate, high, and very high groups, respectively; for PI-RADS score 3 lesions, the rates were 10.5%, 14.3%, 25.0%, and 33.3%, respectively. MRI-guided pathway and risk-based pathway with a low threshold missed only 1.6% csPCa with a biopsy-avoidance rate of 54.4%, and the risk-based pathway with a higher threshold avoided 62.9% (1292/2055) of biopsies with 2.9% (61/2055) missed csPCa detection. Decision curve analysis found that the "risk-based low threshold" pathway has the highest net benefit for probability thresholds between 3.6% and 13.9%.

CONCLUSION

Combined MRI and PSA-density risk-based pathways can be a helpful decision-making tool enabling high csPCa detection rates with the benefit of biopsy avoidance and reduced iPCa detection.

ADVANCES IN KNOWLEDGE

This real-world dataset from a large UK-based cohort confirms that combining MRI scoring with PSA density for risk stratification enables safe biopsy avoidance and limits the over-diagnosis of insignificant cancers.

Targeted augmented reality-guided transperineal prostate biopsies study: initial experience

Background

Transperineal biopsy of magnetic resonance imaging (MRI)-detected prostate lesions is now the established technique used in prostate cancer (CaP) diagnostics. Virtual Surgery Intelligence (VSI) Holomedicine by Apoqlar (Hamburg, Germany) is a mixed reality (MR)/augmented reality (AR) software platform that runs on the HoloLens II system (Microsoft, Redford, USA). Multiparametric prostate MRI images were converted into 3D holograms and added into a MR space, enabling visualization of a 3D hologram and image-assisted prostate biopsy.

Objective

The Targeted Augmented Reality-GuidEd Transperineal (TARGET) study investigated the feasibility of performing AR-guided prostate biopsies in a MR framework, using the VSI platform in patients with MRI-detected prostate lesions.

Methods

Ten patients with a clinical suspicion of CaP on MRI (Prostate Imaging-Reporting and Data System, PI-RADS 4/5) were uploaded to the VSI HoloLens system. Two MR/AR-guided prostate biopsies were then acquired using the PrecisionPoint Freehand transperineal biopsy system. Cognitive fusion biopsies were performed as standard of care following the MR/AR-guided prostate biopsies.

Results

All 10 patients successfully underwent MR/AR-guided prostate biopsy after 3D MR images were overlaid on the patient's body. Prostatic tissue was obtained in all MR/AR-guided specimens. Seven patients (70%) had matching histology in both the standard and MR/AR-guided biopsies. The remaining three had ISUP (International Society of Urological Pathology) Grade 2 CaP. There were no immediate complications.

Conclusion

We believe this is a world first. The initial feasibility data from the TARGET study demonstrated that an MR/AR-guided prostate biopsy utilizing the VSI Holomedicine system is a viable option in CaP diagnostics. The next stage in development is to combine AR images with real-time needle insertion and to provide further data to formally appraise the sensitivity and specificity of the technique.

Prostate health index can stratify patients with Prostate Imaging Reporting and Data System score 3 lesions on magnetic resonance imaging to reduce prostate biopsies

We aim to evaluate prostate health index as an additional risk-stratification tool in patients with Prostate Imaging Reporting and Data System score 3 lesions on multiparametric magnetic resonance imaging. Men with biochemical or clinical suspicion of having prostate cancer who underwent multiparametric magnetic resonance imaging in two tertiary centers (Queen Mary Hospital and Princess Margaret Hospital, Hong Kong, China) between January 2017 and June 2022 were included. Ultrasound-magnetic resonance imaging fusion biopsies were performed after prostate health index testing. Those who only had Prostate Imaging Reporting and Data System score 3 lesions were further stratified into four prostate health index risk groups and the cancer detection rates were analyzed. Out of the 747 patients, 47.3% had Prostate Imaging Reporting and Data System score 3 lesions only. The detection rate of clinically significant prostate cancer in this group was 15.0%. The cancer detection rates of clinically significant prostate cancer had statistically significant differences 5.3% in prostate health index <25.0, 7.4% in prostate health index 25.0-34.9, 17.9% in prostate health index 35.0-54.9, and 52.6% in prostate health index ≥55.0 (P < 0.01). Among the patients, 26.9% could have avoided a biopsy with a prostate health index <25.0, at the expense of a 5.3% risk of missing clinically significant prostate cancer. Prostate health index could be used as an additional risk stratification tool for patients with Prostate Imaging Reporting and Data System score 3 lesions. Biopsies could be avoided in patients with low prostate health index, with a small risk of missing clinically significant prostate cancer.

Biopsy-free AI-aided precision MRI assessment in prediction of prostate cancer biochemical recurrence

BACKGROUND

To investigate the predictive ability of high-throughput MRI with deep survival networks for biochemical recurrence (BCR) of prostate cancer (PCa) after prostatectomy.

METHODS

Clinical-MRI and histopathologic data of 579 (train/test, 463/116) PCa patients were retrospectively collected. The deep survival network (iBCR-Net) is based on stepwise processing operations, which first built an MRI radiomics signature (RadS) for BCR, and predicted the T3 stage and lymph node metastasis (LN+) of tumour using two predefined AI models. Subsequently, clinical, imaging and histopathological variables were integrated into iBCR-Net for BCR prediction.

RESULTS

RadS, derived from 2554 MRI features, was identified as an independent predictor of BCR. Two predefined AI models achieved an accuracy of 82.6% and 78.4% in staging T3 and LN+. The iBCR-Net, when expressed as a presurgical model by integrating RadS, AI-diagnosed T3 stage and PSA, can match a state-of-the-art histopathological model (C-index, 0.81 to 0.83 vs 0.79 to 0.81, p > 0.05); and has maximally 5.16-fold, 12.8-fold, and 2.09-fold (p < 0.05) benefit to conventional D'Amico score, the Cancer of the Prostate Risk Assessment (CAPRA) score and the CAPRA Postsurgical score.

CONCLUSIONS

AI-aided iBCR-Net using high-throughput MRI can predict PCa BCR accurately and thus may provide an alternative to the conventional method for PCa risk stratification.

Evaluation of the optimal strategy in men with a single unilateral suspicious lesion on MRI undergoing transperineal MRI/ultrasound fusion prostate biopsy

BACKGROUND

Targeting biopsy (TBx) of suspicious lesions combined with random systematic biopsy (SBx) improves detection rates of prostate cancer (PCa) during magnetic resonance imaging (MRI)/ultrasound (US) fusion prostate biopsy. However, this combination increases the number of biopsy cores, prolongs the procedure time, and increases complications and costs, leading to the overdiagnosis of clinically insignificant PCa (ciPCa). This study aims to evaluate the optimal sampling design to achieve a detection rate of clinically significant PCa (csPCa) equal to standard TBx with SBx with fewer biopsy cores.

MATERIALS AND METHODS

Of 508 consecutive men who underwent transperineal MRI/US fusion prostate biopsy at our center between January 2020 and December 2022, 364 patients with a single unilateral suspicious lesion on MRI were included in the study. Three biopsy strategies were randomly selected to evaluate the diagnostic accuracy of PCa detection: (1) TBx with ipsilateral SBx, (2) TBx with contralateral SBx, and (3) TBx only. The PCa detection sensitivity for selected biopsy strategies was compared with the reference standards. The significance of differences in cancer detection between sampling schemes was determined using McNemar's test.

RESULTS

PCa was diagnosed in 182 of 364 men using TBx with bilateral SBx. International Society of Urological Pathology grade group (ISUP GG) ≥ 2 and ISUP GG ≥ 3 PCa was detected in 84/364 (23.1%) and 42/364 (11.5%), respectively, while ISUP GG 1 PCa was diagnosed in 98/364 (26.9%). Combining TBx with ipsilateral SBx detected 94.5% of all, 98.8% of ISUP GG ≥ 2, 100% of ISUP GG ≥ 3, and 89.8% of ISUP GG 1 PCa. TBx with contralateral SBx detected fewer csPCa (91.7% vs. 98.8%, p = 0.03), as did TBx alone (90.5 vs. 98.8, p = 0.008).

CONCLUSIONS

Our study demonstrates that TBx with ipsilateral SBx performed around the multiparametric MRI-suspected lesion in transperineal MRI/US biopsy of the prostate achieves a very high detection rate for csPCa (ISUP ≥ 2) without compromising the detection of increased risk PCa (ISUP ≥ 3). In addition, this strategy reduces the number of biopsy cores by 8-10 per patient, procedure time, and pathology processing costs and decreases ciPCa detection.

Ultrasound fusion imaging for improving diagnostic and therapeutic strategies of focal liver lesions: A preliminary study

PURPOSE

To assess the effect of ultrasound (US) fusion imaging on the clinical diagnostic and therapeutic strategies of focal liver lesions, which are difficult to detect or diagnose by conventional US.

METHODS

From November 2019 to June 2022, 71 patients with invisible or undiagnosed focal liver lesions who underwent fusion imaging combining US with CT or MR were included in this retrospective study. The reasons for US fusion imaging were as follows: (1) lesions that were undetectable or inconspicuous on B-mode US; (2) post-ablation lesions that could not be assessed accurately by B-mode US; (3) to evaluate whether the lesions detected by B-mode US that were consistent with those presented on MRI/CT images.

RESULTS

Of the 71 cases, 43 cases were single lesions, and 28 cases were multiple lesions. Among the 46 cases which were invisible on conventional US, the display rate of lesions using US-CT/MRI fusion imaging was 30.8%, and that combined with CEUS was 76.9%. US-guided biopsy was performed in 30 patients after the detection and localization determined by fusion imaging, with a positive rate of 73.3%. Six patients with recurrence after ablation therapy were all detected and located accurately after fusion imaging, and 4 of them successfully underwent ablation therapy again.

CONCLUSION

Fusion imaging contributes to the understanding of the anatomical relationship between lesion location and blood vessels. Additionally, fusion imaging can improve the diagnostic confidence, be helpful to guide interventional operations, and hence be conducive to clinical therapeutic strategies.

PI-RADSAI: introducing a new human-in-the-loop AI model for prostate cancer diagnosis based on MRI

BACKGROUND

This study aims to develop and validate an artificial intelligence (AI)-aided Prostate Imaging Reporting and Data System (PI-RADSAI) for prostate cancer (PCa) diagnosis based on MRI.

METHODS

The deidentified MRI data of 1540 biopsy-naïve patients were collected from four centres. PI-RADSAI is a two-stage, human-in-the-loop AI capable of emulating the diagnostic acumen of subspecialists for PCa on MRI. The first stage uses a UNet-Seg model to detect and segment biopsy-candidate prostate lesions, whereas the second stage leverages UNet-Seg segmentation is trained specifically with subspecialist' knowledge-guided 3D-Resnet to achieve an automatic AI-aided diagnosis for PCa.

RESULTS

In the independent test set, UNet-Seg identified 87.2% (628/720) of target lesions, with a Dice score of 44.9% (range, 22.8-60.2%) in segmenting lesion contours. In the ablation experiment, the model trained with the data from three centres was superior (kappa coefficient, 0.716 vs. 0.531) to that trained with single-centre data. In the internal and external tests, the triple-centre PI-RADSAI model achieved an overall agreement of 58.4% (188/322) and 60.1% (92/153) with a referential subspecialist in scoring target lesions; when one-point margin of error was permissible, the agreement rose to 91.3% (294/322) and 97.3% (149/153), respectively. In the paired test, PI-RADSAI outperformed 5/11 (45.5%) and matched the performance of 3/11 (27.3%) general radiologists in achieving a clinically significant PCa diagnosis (area under the curve, internal test, 0.801 vs. 0.770, p < 0.01; external test, 0.833 vs. 0.867, p = 0.309).

CONCLUSIONS

Our closed-loop PI-RADSAI outperforms or matches the performance of more than 70% of general readers in the MRI assessment of PCa. This system might provide an alternative to radiologists and offer diagnostic benefits to clinical practice, especially where subspecialist expertise is unavailable.

Generative Adversarial Networks Can Create High Quality Artificial Prostate Cancer Magnetic Resonance Images

The recent integration of open-source data with machine learning models, especially in the medical field, has opened new doors to studying disease progression and/or regression. However, the ability to use medical data for machine learning approaches is limited by the specificity of data for a particular medical condition. In this context, the most recent technologies, like generative adversarial networks (GANs), are being looked upon as a potential way to generate high-quality synthetic data that preserve the clinical variability of a condition. However, despite some success, GAN model usage remains largely minimal when depicting the heterogeneity of a disease such as prostate cancer. Previous studies from our group members have focused on automating the quantitative multi-parametric magnetic resonance imaging (mpMRI) using habitat risk scoring (HRS) maps on the prostate cancer patients in the BLaStM trial. In the current study, we aimed to use the images from the BLaStM trial and other sources to train the GAN models, generate synthetic images, and validate their quality. In this context, we used T2-weighted prostate MRI images as training data for Single Natural Image GANs (SinGANs) to make a generative model. A deep learning semantic segmentation pipeline trained the model to segment the prostate boundary on 2D MRI slices. Synthetic images with a high-level segmentation boundary of the prostate were filtered and used in the quality control assessment by participating scientists with varying degrees of experience (more than ten years, one year, or no experience) to work with MRI images. Results showed that the most experienced participating group correctly identified conventional vs. synthetic images with 67% accuracy, the group with one year of experience correctly identified the images with 58% accuracy, and the group with no prior experience reached 50% accuracy. Nearly half (47%) of the synthetic images were mistakenly evaluated as conventional. Interestingly, in a blinded quality assessment, a board-certified radiologist did not significantly differentiate between conventional and synthetic images in the context of the mean quality of synthetic and conventional images. Furthermore, to validate the usability of the generated synthetic images from prostate cancer MRIs, we subjected these to anomaly detection along with the original images. Importantly, the success rate of anomaly detection for quality control-approved synthetic data in phase one corresponded to that of the conventional images. In sum, this study shows promise that high-quality synthetic images from MRIs can be generated using GANs. Such an AI model may contribute significantly to various clinical applications which involve supervised machine-learning approaches.

High-throughput precision MRI assessment with integrated stack-ensemble deep learning can enhance the preoperative prediction of prostate cancer Gleason grade

BACKGROUND

To develop and test a Prostate Imaging Stratification Risk (PRISK) tool for precisely assessing the International Society of Urological Pathology Gleason grade (ISUP-GG) of prostate cancer (PCa).

METHODS

This study included 1442 patients with prostate biopsy from two centres (training, n = 672; internal test, n = 231 and external test, n = 539). PRISK is designed to classify ISUP-GG 0 (benign), ISUP-GG 1, ISUP-GG 2, ISUP-GG 3 and ISUP GG 4/5. Clinical indicators and high-throughput MRI features of PCa were integrated and modelled with hybrid stacked-ensemble learning algorithms.

RESULTS

PRISK achieved a macro area-under-curve of 0.783, 0.798 and 0.762 for the classification of ISUP-GGs in training, internal and external test data. Permitting error ±1 in grading ISUP-GGs, the overall accuracy of PRISK is nearly comparable to invasive biopsy (train: 85.1% vs 88.7%; internal test: 85.1% vs 90.4%; external test: 90.4% vs 94.2%). PSA ≥ 20 ng/ml (odds ratio [OR], 1.58; p = 0.001) and PRISK ≥ GG 3 (OR, 1.45; p = 0.005) were two independent predictors of biochemical recurrence (BCR)-free survival, with a C-index of 0.76 (95% CI, 0.73-0.79) for BCR-free survival prediction.

CONCLUSIONS

PRISK might offer a potential alternative to non-invasively assess ISUP-GG of PCa.

Vector Prostate Biopsy: A Novel Magnetic Resonance Imaging/Ultrasound Image Fusion Transperineal Biopsy Technique Using Electromagnetic Needle Tracking Under Local Anaesthesia

BACKGROUND

Prostate magnetic resonance imaging (MRI) is now standard for assessment of suspected prostate cancer (PCa). A variety of approaches to MRI-based targeting has revolutionised prostate biopsies.

OBJECTIVE

To describe the procedure and show the accuracy and tolerability of a novel Vector MRI/ultrasound fusion transperineal (TP) biopsy technique that uses electromagnetic (EM) needle tracking under local anaesthesia (LA).

DESIGN, SETTING, AND PARTICIPANTS

Vector prostate biopsy using BiopSee fusion software, EM tracking technology, and transrectal ultrasound was performed in 69 patients meeting the biopsy criteria in two UK centres between September 2020 and August 2022.

SURGICAL PROCEDURE

Stepper-mounted rectal ultrasound images were fused with MRI scans. LA was applied into two defined perineal tracks and a needle sheath with an EM sensor was inserted. The biopsy needle was directed precisely through the sheath to MRI targets under EM tracking. Biopsies were taken without antibiotic prophylaxis.

MEASUREMENTS

Cancer detection (any PCa; grade group ≥2), side effects, and patient experience measures were recorded.

RESULTS AND LIMITATIONS

Cancer detection in patients with Likert 4-5 lesions was 98% for any PCa and 83% for grade group ≥2. According to the 50 questionnaires returned, 42 patients (84%) reported no or minimal pain, while 40 (80%) reported no or minimal discomfort. No episodes of postoperative urinary retention occurred, and only one patient required treatment for infection. Limitations include the low patient number and incomplete responses to questionnaires.

CONCLUSIONS

This novel Vector technique provides a feasible and tolerable procedure for MRI/ultrasound fusion TP biopsy under LA, with high cancer detection rates. This is achieved while maintaining patient comfort and with minimal rates of complications.

PATIENT SUMMARY

We report a novel technique that uses electromagnetic needle tracking to perform highly accurate and comfortable prostate biopsies through the perineum under local anaesthetic.

Sub-differentiation of PI-RADS 3 lesions in TZ by advanced diffusion-weighted imaging to aid the biopsy decision process

Background

Performing biopsy for intermediate lesions with PI-RADS 3 has always been controversial. Moreover, it is difficult to differentiate prostate cancer (PCa) and benign prostatic hyperplasia (BPH) nodules in PI-RADS 3 lesions by conventional scans, especially for transition zone (TZ) lesions. The purpose of this study is sub-differentiation of transition zone (TZ) PI-RADS 3 lesions using intravoxel incoherent motion (IVIM), stretched exponential model, and diffusion kurtosis imaging (DKI) to aid the biopsy decision process.

Methods

A total of 198 TZ PI-RADS 3 lesions were included. 149 lesions were BPH, while 49 lesions were PCa, including 37 non-clinical significant PCa (non-csPCa) lesions and 12 clinical significant PCa (csPCa) lesions. Binary logistic regression analysis was used to examine which parameters could predict PCa in TZ PI-RADS 3 lesions. The ROC curve was used to test diagnostic efficiency in distinguishing PCa from TZ PI-RADS 3 lesions, while one-way ANOVA analysis was used to examine which parameters were statistically significant among BPH, non-csPCa and csPCa.

Results

The logistic model was statistically significant (χ2 = 181.410, p<0.001) and could correctly classify 89.39% of the subjects. Parameters of fractional anisotropy (FA) (p=0.004), mean diffusion (MD) (p=0.005), mean kurtosis (MK) (p=0.015), diffusion coefficient (D) (p=0.001), and distribute diffusion coefficient (DDC) (p=0.038) were statistically significant in the model. ROC analysis showed that AUC was 0.9197 (CI 95%: 0.8736-0.9659). Sensitivity, specificity, positive predictive value and negative predictive value were 92.1%, 80.4%, 93.9% and 75.5%, respectively. FA and MK of csPCa were higher than those of non-csPCa (all p<0.05), while MD, ADC, D, and DDC of csPCa were lower than those of non-csPCa (all p<0.05).

Conclusion

FA, MD, MK, D, and DDC can predict PCa in TZ PI-RADS 3 lesions and inform the decision-making process of whether or not to perform a biopsy. Moreover, FA, MD, MK, D, DDC, and ADC may have ability to identify csPCa and non-csPCa in TZ PI-RADS 3 lesions.

Performance of multiparametric prostate magnetic resonance imaging validated by targeted and systematic transperineal biopsies

Objective

To measure the performance of multiparametric (mp) magnetic resonance imaging (MRI) to identify intraprostatic tumour deposits using a systematic and targeted MR-guided transperineal prostate biopsy technique.

Materials and Methods

Patients underwent a combined systematic and targeted MR-guided transperineal biopsy procedure in the dorsal lithotomy position under general anaesthesia. Systematic biopsies were spaced 10 mm or less apart and additional biopsies targeted any Prostate Imaging-Reporting and Data System (PI-RADS) 3, 4 or 5 lesions identified on mpMRI. Cancer detection rates were calculated on a per patient and per lesion basis.

Results

A total of 125 patients underwent the biopsy procedure. The positive predictive value (PPV) of mpMRI per patient was 59% for any cancer and 49% for Gleason score (GS) ≥ 7 cancer. The negative predictive value (NPV) of mpMRI per patient was 67% for any cancer and 88% for GS ≥ 7 cancer. On a per lesion basis, the PPV of PI-RADS 3 lesions for any and GS ≥ 7 cancer was 24% and 10%. For PI-RADS 4 lesions it was 42% and 32%. For PI-RADS 5 lesions, it was 76% and 70%. MpMRI failed to identify GS ≥ 7 cancer found on systematic biopsy in 22% of patients.

Conclusion

Based on a combination of systematic and targeted transperineal prostate biopsies, mpMRI showed a high NPV and low PPV for GS ≥ 7 cancer on a per patient basis. The PPV of mpMRI on a per lesion basis increased with increasing PI-RADS score. However, there were a significant number of both false positive as well as false negative (mpMRI invisible) areas within the prostate that contained GS ≥ 7 cancer. Therefore, pathologic confirmation using both targeted and systematic mapping biopsy is necessary to accurately identify all intraprostatic tumour deposits.

Quality checkpoints in the MRI-directed prostate cancer diagnostic pathway

Multiparametric MRI of the prostate is now recommended as the initial diagnostic test for men presenting with suspected prostate cancer, with a negative MRI enabling safe avoidance of biopsy and a positive result enabling MRI-directed sampling of lesions. The diagnostic pathway consists of several steps, from initial patient presentation and preparation to performing and interpreting MRI, communicating the imaging findings, outlining the prostate and intra-prostatic target lesions, performing the biopsy and assessing the cores. Each component of this pathway requires experienced clinicians, optimized equipment, good inter-disciplinary communication between specialists, and standardized workflows in order to achieve the expected outcomes. Assessment of quality and mitigation measures are essential for the success of the MRI-directed prostate cancer diagnostic pathway. Quality assurance processes including Prostate Imaging-Reporting and Data System, template biopsy, and pathology guidelines help to minimize variation and ensure optimization of the diagnostic pathway. Quality control systems including the Prostate Imaging Quality scoring system, patient-level outcomes (such as Prostate Imaging-Reporting and Data System MRI score assignment and cancer detection rates), multidisciplinary meeting review and audits might also be used to provide consistency of outcomes and ensure that all the benefits of the MRI-directed pathway are achieved.

Radiomics in PI-RADS 3 Multiparametric MRI for Prostate Cancer Identification: Literature Models Re-Implementation and Proposal of a Clinical-Radiological Model

PI-RADS 3 prostate lesions clinical management is still debated, with high variability among different centers. Identifying clinically significant tumors among PI-RADS 3 is crucial. Radiomics applied to multiparametric MR (mpMR) seems promising. Nevertheless, reproducibility assessment by external validation is required. We retrospectively included all patients with at least one PI-RADS 3 lesion (PI-RADS v2.1) detected on a 3T prostate MRI scan at our Institution (June 2016-March 2021). An MRI-targeted biopsy was used as ground truth. We assessed reproducible mpMRI radiomic features found in the literature. Then, we proposed a new model combining PSA density and two radiomic features (texture regularity (T2) and size zone heterogeneity (ADC)). All models were trained/assessed through 100-repetitions 5-fold cross-validation. Eighty patients were included (26 with GS ≥ 7). In total, 9/20 T2 features (Hector's model) and 1 T2 feature (Jin's model) significantly correlated to biopsy on our dataset. PSA density alone predicted clinically significant tumors (sensitivity: 66%; specificity: 71%). Our model obtained a sensitivity of 80% and a specificity of 76%. Standard-compliant works with detailed methodologies achieve comparable radiomic feature sets. Therefore, efforts to facilitate reproducibility are needed, while complex models and imaging protocols seem not, since our model combining PSA density and two radiomic features from routinely performed sequences appeared to differentiate clinically significant cancers.

Performance of Artificial Intelligence-Aided Diagnosis System for Clinically Significant Prostate Cancer with MRI: A Diagnostic Comparison Study

BACKGROUND

The high level of expertise required for accurate interpretation of prostate MRI.

PURPOSE

To develop and test an artificial intelligence (AI) system for diagnosis of clinically significant prostate cancer (CsPC) with MRI.

STUDY TYPE

Retrospective.

SUBJECTS

One thousand two hundred thirty patients from derivation cohort between Jan 2012 and Oct 2019, and 169 patients from a publicly available data (U-Net: 423 for training/validation and 49 for test and TrumpeNet: 820 for training/validation and 579 for test).

FIELD STRENGTH/SEQUENCE

3.0T/scanners, T₂ -weighted imaging (T₂ WI), diffusion-weighted imaging, and apparent diffusion coefficient map.

ASSESSMENT

Close-loop AI system was trained with an Unet for prostate segmentation and a TrumpetNet for CsPC detection. Performance of AI was tested in 410 internal and 169 external sets against 24 radiologists categorizing into junior, general and subspecialist group. Gleason score >6 was identified as CsPC at pathology.

STATISTICAL TESTS

Area under the receiver operating characteristic curve (AUC-ROC); Delong test; Meta-regression I² analysis.

RESULTS

In average, for internal test, AI had lower AUC-ROC than subspecialists (0.85 vs. 0.92, P < 0.05), and was comparable to junior (0.84, P = 0.76) and general group (0.86, P = 0.35). For external test, both AI (0.86) and subspecialist (0.86) had higher AUC than junior (0.80, P < 0.05) and general reader (0.83, P < 0.05). In individual, it revealed moderate diagnostic heterogeneity in 24 readers (Mantel-Haenszel I²  = 56.8%, P < 0.01), and AI outperformed 54.2% (13/24) of readers in summary ROC analysis. In multivariate test, Gleason score, zonal location, PI-RADS score and lesion size significantly impacted the accuracy of AI; while effect of data source, MR device and parameter settings on AI performance is insignificant (P > 0.05).

DATA CONCLUSION

Our AI system can match and to some case exceed clinicians for the diagnosis of CsPC with prostate MRI.

EVIDENCE LEVEL

3 TECHNICAL EFFICACY: Stage 2.

An Magnetic Resonance Imaging–directed Targeted-plus-perilesional Biopsy Approach for Prostate Cancer Diagnosis: “Less Is More”

Background

Considering that most men benefit diagnostically from increased sampling of index lesions, limiting systematic biopsy (SBx) to the region around the index lesion could potentially minimize overdetection while maintaining the detection of clinically significant prostate cancer (csPCa).

Objective

To evaluate the diagnostic performance of a hypothetical magnetic resonance imaging (MRI)-directed targeted-plus-perilesional biopsy approach.

Design, setting, and participants

This single-center, retrospective analysis of prospectively generated data included all biopsy-naïve men with unilateral MRI-positive lesions (Prostate Imaging Reporting and Data System category ≥3), undergoing both MRI-directed targeted biopsies and SBx. Grade group 2–5 cancers were considered csPCa.

Outcome measurements and statistical analysis

The diagnostic performance of a targeted-plus-perilesional biopsy approach was compared with that of a targeted-plus-systematic biopsy approach. The primary outcome was the detection of csPCa. Secondary outcomes included the detection of clinically insignificant prostate cancer (ciPCa) and the number of total biopsy cores.

Results and limitations

A total of 235 men were included in the analysis; csPCa and ciPCa were detected, respectively, in 95 (40.4%) and 86 (36.6%) of these 235 men. A targeted-plus-perilesional biopsy approach would have detected 92/95 (96.8%; 95% confidence interval [CI] 91.0–99.3%) csPCa cases. At the same time, detection of systematically found ciPCa would be reduced by 11/86 (12.8%; 95% CI 6.6–21.7%). If a targeted-plus-perilesional biopsy approach would have been performed, the number of biopsy cores per patient would have been reduced significantly (a mean difference of 5.2; 95% CI 4.9–5.6, p < 0.001).

Conclusions

An MRI-directed targeted-plus-perilesional biopsy approach detected almost all csPCa cases, while limiting overdiagnosis and reducing the number of biopsy cores. Prospective clinical trials are needed to substantiate the withholding of nonperilesional SBx in men with unilateral lesion(s) on MRI.

Patient summary

Limiting systematic biopsies to the proximity of the suspicious area on magnetic resonance imaging helps detect an equivalent number of aggressive cancers and fewer indolent cancers. These findings may help patients and physicians choose the best biopsy approach.

The impact of health-policy-driven subsidisation of prostate magnetic resonance imaging on transperineal prostate biopsy practice and outcomes

Background

From 1 July 2018, the Australian Medicare Benefits Schedule (MBS) introduced rebates for multi-parametric magnetic resonance imaging (mpMRI) for the workup for prostate cancer (PCa). We aimed to determine if subsidisation of mpMRI prior to transperineal biopsy altered our institution's prostate biopsy practice patterns and outcomes.

Methods

All patients who underwent transperineal prostate biopsy at an Australian tertiary institution from 1 January 2017 to 1 January 2020 were identified. Patients with known PCa were excluded. Patients were stratified into two groups: a pre-subsidisation cohort comprising patients biopsied prior to the introduction of mpMRI subsidisation on 1 July 2018 and a post-subsidisation cohort comprising patients biopsied after 1 July 2018. Histopathological results were compared with further stratification based on mpMRI results. Clinically significant cancer was defined as ISUP Grade Group ≥ 2.

Results

Six hundred and fifty men fulfilled the inclusion criteria. Three hundred and sixty-one patients were in the pre-subsidisation cohort and 289 in the post-subsidisation cohort. Of the patients in the pre-subsidisation group, 36.3% underwent a pre-biopsy mpMRI compared with 77.5% in the post-subsidisation group. Of the patients in the pre-subsidisation group, 59.6% had positive biopsies (p = 0.024) compared with 68.2% in the post-subsidisation group. The rate of clinically significant PCa was lower in the pre-subsidisation group (39.1%) compared with the post-subsidisation (49.5%, p = 0.008). The negative predictive value of mpMRI for clinically significant PCa was 86.5%.

Conclusion

Our institution experienced a reduction of negative prostate biopsies and an increase in clinically significant PCa within transperineal biopsy specimens after the Australian healthcare system introduced financial subsidisation of mpMRI.

A clinical available decision support scheme for optimizing prostate biopsy based on mpMRI

BACKGROUND

Combined MRI/Ultrasound fusion targeted biopsy (TBx) and systematic biopsy (SBx) results in better prostate cancer (PCa) detection relative to either TBx or SBx alone, while at the cost of higher number of biopsy cores and greater detection of clinically insignificant PCa. We therefore developed and evaluated a simple decision support scheme for optimizing prostate biopsy based on multiparametric (mp) MRI assessment.

METHODS

Total 229 patients with suspicion of PCa underwent mpMRI before combined TBx/SBx were retrospectively included. Impacts of MRI characteristics such as Prostate Imaging-Reporting and Data System (PI-RADS) score, lesion size, zonal origination, and location on biopsy performance were evaluated. A clinically available decision support scheme relying on mpMRI assessment was subsequently developed as a triage test to optimize prostate biopsy process. Cost (downgrade, upgrade, and biopsy core)-to-Effectiveness (detection rate) was systemically compared.

RESULTS

TBx achieved comparable detection rate to combined TBx/SBx in diagnosis of PCa and clinically significant PCa (csPCa) (PCa, 59% [135/229] vs 60.7% [139/229]; csPCa, 45.9% [105/229] vs 47.2% [108/229]; p-values > 0.05) and outperformed SBx (PCa, 42.4% [97/229]; csPCa, 28.4% [65/229]; p-values < 0.001). Specially, in personalized decision support scheme, TBx accurately detected all PCa (72.5% [74/102]) in PI-RADS 5 and larger (≥1 cm) PI-RADS 3-4 observations, adding SBx to TBx only resulted in 1.4% (1/74) upgrading csPCa. For smaller (<1 cm) PI-RADS 3-4 lesions, combined TBx/SBx resulted in relatively higher detection rate (51.2% [65/127] vs 48.0% [61/127]) and lower upgrading rate (30.6% [15/49] vs 36.7% [18/49]) than TBx.

CONCLUSIONS

The benefit of SBx added to TBx was largely restricted to smaller PI-RADS score 3-4 lesions. Using our personalized strategy of solo TBx for PI-RADS 5 and larger (≥1 cm) PI-RADS score 3-4 lesions would avoid excess SBx in 44.5% (102/229) of all biopsy-naïve patients without compromising detection rate.

Time-Dependent Diffusion MRI for Quantitative Microstructural Mapping of Prostate Cancer

Background Recently developed time-dependent diffusion MRI has potential in characterizing cellular tissue microstructures; however, its value in imaging prostate cancer (PCa) remains unknown. Purpose To investigate the feasibility of time-dependent diffusion MRI-based microstructural mapping for noninvasively characterizing cellular properties of PCa and for discriminating between clinically significant PCa and clinically insignificant disease. Materials and Methods Men with a clinical suspicion of PCa were enrolled prospectively between October 2019 and August 2020. Time-dependent diffusion MRI data were acquired with pulsed and oscillating gradient diffusion MRI sequences at an equivalent diffusion time of 7.5-30 msec on a 3.0-T scanner. Time-dependent diffusion MRI-based microstructural parameters, including cell diameter, intracellular volume fraction, cellularity, and diffusivities, were estimated with a two-compartment model. These were compared for different International Society of Urological Pathology grade groups (GGs), and their performance in discriminating clinically significant PCa (GG >1) from clinically insignificant disease (benign and GG 1) was determined with a linear discriminant analysis. The fitted microstructural parameters were validated by means of correlation with histopathologic measurements. Results In the 48 enrolled men, the time-dependent diffusion MRI measurements showed that higher GG was correlated with higher intracellular volume fraction and higher cellularity (intracellular volume fraction = 0.22, 0.36, 0.34, 0.37, and 0.40 in GGs 1-5, respectively; P < .001 at one-way analysis of variance), while lower cell diameter was found at higher GGs (diameter = 23.4, 18.3, 19.2, 17.9, and 18.5 μm in GGs 1-5, respectively; P = .002). Among all measurements derived from time-dependent diffusion MRI, cellularity achieved the highest diagnostic performance, with an accuracy of 92% (44 of 48 participants) and area under the receiver operating characteristic curve of 0.96 (95% CI: 0.87, 0.99) in discriminating clinically significant PCa from clinically insignificant disease. Microstructural mapping was supported by positive correlations between time-dependent diffusion MRI-based and pathologic examination-based intracellular volume fraction (r = 0.83; P < .001). Conclusion Time-dependent diffusion MRI-based microstructural mapping correlates with pathologic findings and demonstrates promise for characterizing prostate cancer. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Chatterjee and Oto in this issue.

Optimal biopsy approach for detection of clinically significant prostate cancer

Prostate cancer (PCa) diagnostic and therapeutic work-up has evolved significantly in the last decade, with pre-biopsy multiparametric MRI now widely endorsed within international guidelines. There is potential to move away from the widespread use of systematic biopsy cores and towards an individualised risk-stratified approach. However, the evidence on the optimal biopsy approach remains heterogeneous, and the aim of this review is to highlight the most relevant features following a critical assessment of the literature. The commonest biopsy approaches are via the transperineal (TP) or transrectal (TR) routes. The former is considered more advantageous due to its negligible risk of post-procedural sepsis and reduced need for antimicrobial prophylaxis; the more recent development of local anaesthetic (LA) methods now makes this approach feasible in the clinic. Beyond this, several techniques are available, including cognitive registration, MRI-Ultrasound fusion imaging and direct MRI in-bore guided biopsy. Evidence shows that performing targeted biopsies reduces the number of cores required and can achieve acceptable rates of detection whilst helping to minimise complications and reducing pathologist workloads and costs to health-care facilities. Pre-biopsy MRI has revolutionised the diagnostic pathway for PCa, and optimising the biopsy process is now a focus. Combining MR imaging, TP biopsy and a more widespread use of LA in an outpatient setting seems a reasonable solution to balance health-care costs and benefits, however, local choices are likely to depend on the expertise and experience of clinicians and on the technology available.

A Combined CRISP3 and SPINK1 Prognostic Grade in EPS-Urine and Establishment of Models to Predict Prognosis of Patients With Prostate Cancer

Background

Prostate cancer (PCa) is characterized by significant heterogeneity. Thus, novel prognostic indicators are required to improve prognosis and treatment.

Methods

Cysteine rich secretory protein 3 (CRISP3) and serine peptidase inhibitor Kazal type 1 (SPINK1) levels in expressed prostatic secretion (EPS)-urine collected during digital rectal examination of 496 patients histologically diagnosed with PCa were detected via enzyme-linked immunosorbent assay. A combined CRISP3 and SPINK1 prognostic grade (CSPG) was defined using cut-off values from receiver operating characteristic curves. Log-rank Kaplan-Meier survival curves investigated differences in prognosis between groups. Univariate and multivariate Cox analyses investigated the CSPG relationship with biochemical recurrence (BCR), cancer-specific survival (CSS), and overall survival (OS). Three prognostic models were developed and validated.

Conclusions

CRISP3 and SPINK1 levels increased with Gleason score progression, pathological T stage, and metastasis status. CSPG in EPS-urine, which was an effective independent prognostic variable, accurately predicted the prognosis of patients with PCa. Three clinical prognostic models using the CSPG for BCR, CSS, and OS were developed and validated.

Evidence-based guideline recommendations on multiparametric magnetic resonance imaging in the diagnosis of clinically significant prostate cancer: A Cancer Care Ontario updated clinical practice guideline

INTRODUCTION

This clinical practice guideline is based on a systematic review to assess the use of multiparametric magnetic resonance imaging (mpMRI) in the diagnosis of clinically significant prostate cancer (csPCa) for biopsy-naive men and men with a prior negative transrectal ultrasound-guided systematic biopsy (TRUS-SB) at elevated risk.

METHODS

The methods of the clinical practice guideline included searches to September of 2020 of MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials. Internal and external reviews were conducted.

RESULTS

The recommendations are:Recommendation 1: For biopsy-naive patients at elevated risk of csPCa, mpMRI is recommended prior to biopsy in patients who are candidates for curative management with suspected clinically localized prostate cancer.- If the mpMRI is positive, mpMRI-targeted biopsy (TB) and TRUS-SB should be performed together to maximize detection of csPCa.- If the mpMRI is negative, consider forgoing any biopsy after discussion of the risks and benefits with the patient as part of shared decision-making and ongoing followup.Recommendation 2: In patients who had a prior negative TRUS-SB and demonstrate a high risk of having csPCa in whom curative management is being considered:- mpMRI should be performed.- If the mpMRI is positive, targeted biopsy should be performed. Concomitant TRUS-SB can be considered depending on the patient's risk profile and time since prior TRUS-SB biopsy.- If the mpMRI is negative, consider forgoing a TRUS-SB only after discussion of the risks and benefits with the patient as part of shared decision-making and ongoing followup.Recommendation 3: mpMRI should be performed and interpreted in compliance with the current Prostate Imaging Reporting & Data System (PI-RADS) guidelines.

Relationship of prostate cancer topography and tumour conspicuity on multiparametric magnetic resonance imaging: a protocol for a systematic review and meta-analysis

INTRODUCTION

Multiparametric magnetic resonance imaging (mpMRI) has improved the triage of men with suspected prostate cancer, through precision prebiopsy identification of clinically significant disease. While multiple important characteristics, including tumour grade and size have been shown to affect conspicuity on mpMRI, tumour location and association with mpMRI visibility is an underexplored facet of this field. Therefore, the objective of this systematic review and meta-analysis is to collate the extant evidence comparing MRI performance between different locations within the prostate in men with existing or suspected prostate cancer. This review will help clarify mechanisms that underpin whether a tumour is visible, and the prognostic implications of our findings.

METHODS AND ANALYSIS

The databases MEDLINE, PubMed, Embase and Cochrane will be systematically searched for relevant studies. Eligible studies will be full-text English-language articles that examine the effect of zonal location on mpMRI conspicuity. Two reviewers will perform study selection, data extraction and quality assessment. A third reviewer will be involved if consensus is not achieved. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines will inform the methodology and reporting of the review. Study bias will be assessed using a modified Newcastle-Ottawa scale. A thematic approach will be used to synthesise key location-based factors associated with mpMRI conspicuity. A meta-analysis will be conducted to form a pooled value of the sensitivity and specificity of mpMRI at different tumour locations.

ETHICS AND DISSEMINATION

Ethical approval is not required as it is a protocol for a systematic review. Findings will be disseminated through peer-reviewed publications and conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42021228087.

Developments in optimizing transperineal prostate biopsy

PURPOSE OF REVIEW

Prostate biopsy is a very commonly performed office procedure leading to the diagnosis of the most prevalent solid-organ malignancy in American men. Although the transrectal technique for prostate biopsy remains the gold standard, there is increasing interest in the transperineal approach as it offers a clean, percutaneous approach that significantly decreases the risk for infection. In this review, we discuss emerging developments in transperineal prostate biopsy that may optimize the way biopsies are performed in clinical practice.

RECENT FINDINGS

Similarly, to transrectal biopsy, the transperineal approach also allows for the performance of systematic and MRI-targeted biopsy cores. As transperineal biopsy obviates the translocation of rectal bacteria to the prostate or bloodstream, in contrast to transrectal biopsy, it is feasible to forgo peri-procedural antibiotics in accordance with professional guidelines. This may attenuate antimicrobial resistance that may be associated with augmented prophylaxis. In addition, although transperineal biopsy may be traditionally performed under general anesthesia using a template grid, it may also be performed freehand under local anesthesia or sedation. Avoiding prophylactic antibiotics and general anesthesia as well as reducing infections/hospitalizations for transperineal biopsy scaled nationally will likely result in significant healthcare savings.

SUMMARY

Transperineal biopsy with combined systematic and MRI-targeted cores, offers several advantages over conventional transrectal biopsy. Transperineal biopsy under local anesthesia and without periprocedural antibiotic is emerging as a promising method for prostate cancer diagnosis and surveillance.

Multiparametric Magnetic Resonance Imaging for the Detection of Clinically Significant Prostate Cancer: What Urologists Need to Know. Part 4: Transperineal Magnetic Resonance-Ultrasound Fusion Guided Biopsy Using Local Anesthesia

BACKGROUND

Transperineal magnetic resonance imaging-transrectal ultrasound fusion guided biopsy (MFGB) is an increasingly popular technique due to increasing rates of biopsy-related infections. However, its widespread implementation has been hampered by the supposed necessity of epidural or general anesthesia.

OBJECTIVE

To demonstrate the technique, feasibility, and results of transperineal MFGB under local anesthesia, in an ambulatory setting without the administration of prophylactic antibiotics.

DESIGN, SETTING, AND PARTICIPANTS

This single-center study enrolled consecutive biopsy-naïve men with a clinical suspicion of prostate cancer into a prospective database between November 2015 and November 2020. Men with Prostate Imaging Reporting and Data System (PI-RADS) version 2 scores 3-5 underwent transperineal MFGB.

SURGICAL PROCEDURE

Transperineal MFGB was performed in an ambulatory setting under local anesthesia by a single operator.

MEASUREMENTS

Procedure-associated adverse events were recorded. Patient discomfort during both the local anesthesia and the biopsy procedure was determined using a visual analogic scale (0-10). Detection rates of grade group (GG) ≥2 prostate cancer and the proportion of men with GG 1 cancer were assessed.

RESULTS AND LIMITATIONS

A total of 1097 eligible men underwent transperineal MFGB. The complication rate was 0.73% (8/1097); complications comprised five (0.46%) urinary tract infections including one hospitalization and three (0.27%) urinary retentions. In 735 men, the median pain scores were 2 (interquartile range [IQR] 2-3) for the local anesthesia procedure and 1 (IQR 0-2) for the biopsy. Prostate cancer was detected in 84% (926/1097) of men; 66% (723/1097) had GG ≥2 and 19% (203/1097) GG 1.

CONCLUSIONS

Transperineal MFGB can safely be performed as an outpatient procedure under local anesthesia in an ambulatory setting. The detection rate of clinically significant prostate cancer is high, and biopsy is well tolerated. Although no antibiotic prophylaxis was used, the rate of infectious complications is practicably negligible.

PATIENT SUMMARY

This article shows how tissue samples (biopsies) can accurately be obtained from suspicious regions seen on prostate magnetic resonance imaging via needles inserted in the perineum (skin between the scrotum and the anus) in men with suspected prostate cancer. This technique appears to be very well tolerated under local anesthesia and has a lower risk of infection without antibiotic prophylaxis than the more common biopsy route through the rectum, with antibiotics.

Recent Advances in Systematic and Targeted Prostate Biopsies

Prostate biopsy is the definitive investigation to diagnose prostate cancer. The ideal procedure would be one that offers fast and efficient results safely as an outpatient procedure. Historically, transrectal ultrasound (TRUS) biopsy is considered the gold standard but transrectal biopsy can under-sample the anterior and apical regions of the prostate and is associated with a risk of prostate biopsy-related sepsis, which may require intensive care admission. Transperineal (TP) biopsy addresses the inefficient sampling of TRUS biopsy but historically has been done under general anaesthetic, which makes it difficult to incorporate into timed diagnostic pathways such as the National Health Service (NHS) 2-week cancer pathway. TRUS biopsy has remained the mainstay of clinical diagnosis because of its simplicity; however, the recent development of simpler local anaesthetic transperineal techniques has transformed outpatient biopsy practice. These techniques practically eliminate prostate biopsy-related sepsis, have a shallow learning curve and offer effective sampling of all areas of the prostate in an outpatient setting. The effectiveness of TP biopsy has been enhanced by the introduction of multiparametric MRI prior to biopsy, the use of PSA density for risk stratification in equivocal cases and combined with more efficient targeted and systematic biopsies techniques, such as the Ginsburg Protocol, has improved the tolerability and diagnostic yield of local anaesthetic TP biopsies, reducing the risk of complications from the oversampling associated with transperineal template mapping biopsies. Areas where the literature remains unclear is the optimum number of cores needed to detect clinically significant disease (CSD) in patients with a definable lesion on MRI, in particular, whether there is a need for systematic biopsy in the face of equivocal MRI findings to ensure no CSD is missed. The Covid-19 pandemic has had a profound impact on prostate cancer referrals and prostate biopsy techniques within the UK; prior to the pandemic 65% of all prostate biopsies were TRUS, since the pandemic the proportions have reversed such that now over 65% of all prostate biopsies in the NHS are transperineal.

Utility of multiple core biopsies during transperineal template-guided mapping biopsy for patients with large prostates and PI-RADS 1–2 on multiparametric magnetic resonance imaging

Background

We investigated the necessity of multiple core biopsies when performing transperineal template-guided mapping biopsy (TTMB) for patients with large prostates and no suspicious lesions on multiparametric magnetic resonance imaging (mpMRI).

Materials and methods

We retrospectively analyzed 304 patients on active surveillance (AS), 212 patients with previously negative transrectal ultrasound-guided biopsy (TRUS-Bx) and 67 biopsy naïve patients who underwent TTMB between May 2017 and December 2020. The number of core biopsies and acute urinary retention (AUR) rates were analyzed in relation to the prostate volume (PV). Cancer detection rate according to the prostate volume and Prostate Imaging-Reporting and Data System (PI-RADS) scores were compared using the Pearson Chi-square test.

Results

AUR occurred more frequently in patients with PV over 39 cc (5.5% vs. 24.4%, P < 0.001). In addition, incidence of AUR was more in patients with PV over 39 cc and PI-RADS score of 1–2 on mpMRI (3.7% vs. 22.2%, P < 0.001). There was no significant difference in the detection rates of any prostate cancer or clinically significant prostate cancer (csPCA) between the patients on AS with PV < 39 cc and PV ≥ 39 cc and PI-RADS score 1–2 (57.4% vs. 50%, P = 0.507; 17% vs. 8.8%, P = 0.412, respectively). Additionally, no significant difference was found in the detection rates of any prostate cancer or csPCA between the patients with PV < 39 cc and PV ≥ 39 cc and PI-RADS score 1–2 who either had a previously negative TRUS-Bx or were biopsy naïve (27.9% vs. 16.2%, P = 0.101, 8.2% vs. 4.1%, P = 0.31, respectively).

Conclusion

Increasing the number of core biopsies of prostates measuring ≥39 cc with PI-RADS 1–2 on mpMRI does not significantly increase the detection rates of any prostate cancer or csPCA.

Multiparametric Magnetic Resonance Imaging in the Diagnosis of Clinically Significant Prostate Cancer: an Updated Systematic Review

There has been growing utilisation of multiparametric magnetic resonance imaging (MPMRI) as a non-invasive tool to diagnose and localise clinically significant prostate cancer (CSPCa). This updated systematic review examines the use of MPMRI in patients with an elevated risk of CSPCa who have had a prior negative transrectal ultrasound systematic biopsy (TRUS-SB) and who were biopsy naïve. MEDLINE, EMBASE and the Cochrane Database of Systematic Reviews were searched for existing systematic reviews published up to September 2020. The literature search of the electronic databases combined disease-specific terms (prostate cancer, prostate carcinoma, etc.) and treatment-specific terms (magnetic resonance, etc.). Studies were included if they were randomised controlled trials (RCTs) comparing MPMRI to template transperineal mapping biopsy (TPMB) or to TRUS-SB. Thirty-six RCTs were eligible. For biopsy-naïve men, accuracy of diagnosis of CSPCa showed sensitivities from 87 to 96% and specificities ranging from 29 to 45%. Meta-analyses for CSPCa showed increased detection favouring MPMRI-targeted biopsy over TRUS-SB by 3% (95% confidence interval 0-7%, P = 0.03) and decreased detection of clinically insignificant prostate cancer (CISPCa) favouring MPMRI by 8% (95% confidence interval -11 to 5%, P < 0.00001). Accuracy of MPMRI for men with prior negative biopsy showed sensitivities of 78-100% and specificities of 30-100%. Meta-analyses comparing MPMRI to TRUS-SB showed increased detection of 5% (95% confidence interval 3-7%, P < 0.0001) with a reduction of CISPCa detection of 7% (95% confidence interval 4-9%, P < 0.00001). The growing acceptance of MPMRI utilisation internationally and the recent publication of several RCTs regarding MPMRI in reducing CISPCa detection rates, particularly in biopsy-naïve men, without loss of sensitivity for CSPCa necessitates the synthesis of updated evidence examining MPMRI in the diagnosis of CSPCa.

Magnetic Resonance Imaging (MRI)-Targeted Biopsy in Patients with Prostate-Specific Antigen (PSA) Levels <20 ng/mL: A Single-Center Study in Northeastern China

Background

We investigated the feasibility of applying magnetic resonance imaging (MRI)-targeted biopsy (TB) in patients with prostate-specific antigen (PSA) levels <20 ng/mL.

Material/Methods

We retrospectively analyzed 218 patients with PSA levels <20 ng/mL and suspicious lesions according to the Prostate Imaging Recording and Data System version 2.0 (PI-RADS v2). All 218 men underwent transperineal MRI-TB, followed by template-guided 12-core systematic biopsy (SB). Of the 218 patients undergoing TB, 100 received MRI-ultrasound-assisted software fusion biopsy (FB) and 118 received cognitive biopsy (CB). Clinically significant prostate cancer (csPCa) was defined as a Gleason score ≥3+4.

Results

The overall TB positive rate was similar to that of SB (P=0.156), but with a higher diagnostic rate for csPCa (P=0.034). SB misdiagnosed csPCa in 11.47% of cases; TB misdiagnosed csPCa in 5.50% of cases. SB+TB detected more tumors with a Gleason score of 7 than did SB alone (43 vs 22). Detection rates of csPCa were similar for CB and FB (P=0.217). In total, 47 men had 2 MRI-determined suspicious areas. Of 265 suspicious areas, 143 (53.96%) had a PI-RADS v2 score of 3; 92 (34.71%) had a score of 4; and 30 (11.32%) had a score of 5. The positive detection rates for csPCa in patients with PI-RADS v2 scores of 3, 4, and 5, were 11.19%, 48.91%, and 80.00%, respectively.

Conclusions

TB increased the positive biopsy detection rate but missed some cases of csPCa. TB combined with SB may be the most suitable biopsy for patients with PSA <20 ng/mL.

Anterior and apical samplings during transperineal image-guided prostate biopsy

INTRODUCTION

Concurrent systematic biopsies during image-guided targeted biopsies of the prostate were found to improve the detection rate of clinically significant prostate cancer (CSPC). However, these biopsies do not routinely include anterior or apical sampling. We aimed to evaluate the significance of anterior and apical samplings during combined biopsies.

METHODS

After obtaining institutional review board approval we identified 303 consecutive patients who underwent transperineal combined biopsies of the prostate between 2017-2020. Systematic biopsies were obtained from the peripheral zone, anterior zone, and apex. Study outcomes included CSPC and any cancer on anterior or apical biopsies. Logistic regression analyses were used to evaluate the association between pre-biopsy characteristics and study outcomes.

RESULTS

Median prostatic-specific-antigen value was 6.8 ng/dL. Most patients had stage T1c disease (77%). Overall, combined biopsies detected CSPC in 87 patients (29%). Any cancer and CSPC in the anterior zone were found in 54 (18%) and 19 (6%) patients, respectively. Any cancer and CSPC in the apex were found in 54 (18%) and 16 (5%) patients, respectively. Anterior/apical samplings upgraded the pathological result in 19 patients (6%). Logistic regression analyses demonstrated that PI-RADS 5 lesions predicted the presence of CSPC in both the anterior zone (OR = 8, 95%CI = 3-22, P <0.001) and apex (OR = 4, 95%CI = 1-10, P = 0.01).

CONCLUSIONS

Avoiding anterior and apical samplings during prostate biopsy does not result in substantial under-diagnosis of significant cancer. However, these areas are easily accessible using the transperineal approach and should be sampled in selected patients, particularly those with PI-RADS 5 lesions.

Micro-Ultrasound: a way to bring imaging for prostate cancer back to urology

Only a decade ago, there were insufficient imaging options for the detection and local staging of prostate cancer. However, the introduction of multiparametric magnetic resonance imaging (mpMRI) has advanced a much-needed tool for this scope of application. The possibilities and limitations of mpMRI have been well studied. Imaging must be acquired and evaluated using a standardized protocol (the latest version of Prostate Imaging-Reporting and Data System). Sensitivity has been shown to increase with higher grades and larger tumors, and while the detection rate on a per patient basis is relatively high, the per-lesion detection rate is far inferior. Various specialists have attempted to elevate the use of transrectal ultrasound, a tool frequently used by all urologists. Encouragement for this idea comes from a recently introduced system of high frequency transrectal ultrasound. The level of evidence supporting its use in the detection and staging of prostate cancer is not comparable with mpMRI yet, but initial prospective studies indicate good potential. The sensitivity of micro-ultrasound and mpMRI for clinically significant prostate cancer ranges from 94% to 100% and from 88% to 90%, respectively. Further areas of application, such as local staging for prostate and bladder cancer, are currently being evaluated. In summary, microultrasound presents a promising technology for further improving urological imaging and allows for the possibility of returning prostate cancer imaging to urologists. This review will summarize the current scientific basis for the use of micro-ultrasound in the detection of prostate cancer.

MRI-derived PRECISE scores for predicting pathologically-confirmed radiological progression in prostate cancer patients on active surveillance

OBJECTIVES

To assess the predictive value and correlation to pathological progression of the Prostate Cancer Radiological Estimation of Change in Sequential Evaluation (PRECISE) scoring system in the follow-up of prostate cancer (PCa) patients on active surveillance (AS).

METHODS

A total of 295 men enrolled on an AS programme between 2011 and 2018 were included. Baseline multiparametric magnetic resonance imaging (mpMRI) was performed at AS entry to guide biopsy. The follow-up mpMRI studies were prospectively reported by two sub-specialist uroradiologists with 10 years and 13 years of experience. PRECISE scores were dichotomized at the cut-off value of 4, and the sensitivity, specificity, positive predictive value and negative predictive value were calculated. Diagnostic performance was further quantified by using area under the receiver operating curve (AUC) which was based on the results of targeted MRI-US fusion biopsy. Univariate analysis using Cox regression was performed to assess which baseline clinical and mpMRI parameters were related to disease progression on AS.

RESULTS

Progression rate of the cohort was 13.9% (41/295) over a median follow-up of 52 months. With a cut-off value of category ≥ 4, the PRECISE scoring system showed sensitivity, specificity, PPV and NPV for predicting progression on AS of 0.76, 0.89, 0.52 and 0.96, respectively. The AUC was 0.82 (95% CI = 0.74-0.90). Prostate-specific antigen density (PSA-D), Likert lesion score and index lesion size were the only significant baseline predictors of progression (each p < 0.05).

CONCLUSION

The PRECISE scoring system showed good overall performance, and the high NPV may help limit the number of follow-up biopsies required in patients on AS.

KEY POINTS

• PRECISE scores 1-3 have high NPV which could reduce the need for re-biopsy during active surveillance. • PRECISE scores 4-5 have moderate PPV and should trigger either close monitoring or re-biopsy. • Three baseline predictors (PSA density, lesion size and Likert score) have a significant impact on the progression-free survival (PFS) time.

Feature Extraction of Kidney Tissue Image Based on Ultrasound Image Segmentation

The kidney tissue image is affected by other interferences in the tissue, which makes it difficult to extract the kidney tissue image features, and it is difficult to judge the lesion characteristics and types by intelligent feature recognition. In order to improve the efficiency and accuracy of feature extraction of kidney tissue images, refer to the ultrasonic heart image for analysis and then apply it to the feature extraction of kidney tissue. This paper proposes a feature extraction method based on ultrasound image segmentation. Moreover, this study combines the optical flow method and the speckle tracking algorithm to select the best image tracking method and optimizes the algorithm speed through the full search method and the two-dimensional log search method. In addition, this study verifies the performance of the method proposed in this paper through comparative experimental research, and this study combines statistical analysis methods to perform data analysis. The research results show that the algorithm proposed in this paper has a certain effect.

Clash of the calculators: External validation of prostate cancer risk calculators in men undergoing mpMRI and transperineal biopsy

Objective

To compare the accuracy of the European Randomized Study of Screening for Prostate Cancer (ERSPC) RC, MRI‐ERSPC‐RC, and Prostate Biopsy Collaborative Group (PBCG) RC in patients undergoing transperineal prostate biopsy.

Patients and methods

We identified 392 patients who underwent mpMRI before transperineal prostate biopsy across multiple public and private institutions between January 2017 and August 2019. The estimated probabilities of detecting PCa and significant PCa were calculated using the MRI‐ERSPC‐RC, ERSPC‐RC, and PBCG‐RC. Receiver operating characteristic (ROC) curves for each calculator were generated and the area underneath the curve (AUC) was compared. Calibration and clinical utility were assessed with calibration plots and decision curve analysis, respectively.

Results

PCa was detected in 285 patients (72.7%) with significant PCa found in 200 patients (51.1%). ROC curve analysis found the MRI‐ERSPC‐RC outperformed the ERSPC‐RC and PBCG‐RC. For the prediction of PCa, the AUC was 0.756, 0.696, and 0.675 for the MRI‐ERSPC‐RC, ERSPC‐RC, and PBCG‐RC, respectively. The AUC for the prediction of significant PCa was 0.803, 0.745, and 0.746 for the MRI‐ERSPC‐RC, ERSPC‐RC, and PBCG‐RC, respectively.

Conclusions

Our study validated the ERSPC‐RC, MRI‐ERSPC‐RC, and PBCG‐RC in a cohort undergoing transperineal prostate biopsy with the MRI‐ERSPC‐RC performing the best. These RCs may enable improved shared decision making and help to guide patient selection for biopsy.

Comparison of initial and second opinion reads of multiparametric magnetic resonance imaging of the prostate for transperineal template-guided biopsies with MRI-Ultrasound fusion

PURPOSE

To investigate the value of second-opinion evaluation of multiparametric prostate magnetic resonance imaging (MRI) by subspecialised uroradiologists for the detection of significant cancer in transperineal fusion prostate biopsy.

METHODS

The evaluated data included age, PSA (ng/ml), PSA density, Gleason score, digital rectal examination (DRE), prostate volume of 149 patients. Twenty-seven patients (18%) had no previous prostate biopsy, 114 patients (77%) had a previous negative biopsy, and 8 patients (5%) were on active surveillance. Using PI-RADS v2 scores for mpMRI a second report was performed by a specialist uroradiologist. In all cases a subsequent transperineal biopsy was performed with at least 2 cores per target and additional background systemic cores. Initial and second-opinion radiology reports were evaluated for detection of any cancer and Gleason score (GS) 7-10 cancer, including positive predictive value and negative (NPV) and compared by Fisher's exact test.

RESULTS

At transperineal biopsy, 51 % (76/149) of patients had a GS 6-10 prostate cancer (PCa), 27 % (40/149) of patients had a GS 3 + 3 PCa and 12 % (18/149) a GS 3 + 4 and 12 % (18/149) had a GS ≥4 + 3 PCa. Agreement between initial and second-opinion reads was observed in 57.7% (86/149; kappa value = 0.32). The detection of clinically significant cancers with second-opinion reads was significantly higher (0.61; 17/28) compared to initial reads (0.35; 17/49); P = 0.034.

CONCLUSIONS

Second reading of prostate mpMRIs by subspecialised uroradiologists significantly improved the positive predictive value for detection of clinically significant prostate cancer and showed a trend towards improved NPV for MRI-negative cases where biopsy could be safely avoided. Urologists should be aware that the experience of the reporter will affect the report when making decisions if and how to obtain biopsies. Reporter experience may help to reduce overcalling and avoid over-targeting of lesions.

A novel nomogram predicting lymph node invasion among patients with prostate cancer: The importance of extracapsular extension at multiparametric magnetic resonance imaging

PURPOSE

To develop a novel risk tool that allows the prediction of lymph node invasion (LNI) among patients with prostate cancer (PCa) treated with robot-assisted radical prostatectomy (RARP) and extended pelvic lymph node dissection (ePLND).

METHODS

We retrospectively identified 742 patients treated with RARP + ePLND at a single center between 2012 and 2018. All patients underwent multiparametric magnetic resonance imaging (mpMRI) and were diagnosed with targeted biopsies. First, the nomogram published by Briganti et al. was validated in our cohort. Second, three novel multivariable logistic regression models predicting LNI were developed: (1) a complete model fitted with PSA, ISUP grade groups, percentage of positive cores (PCP), extracapsular extension (ECE), and Prostate Imaging Reporting and Data System (PI-RADS) score; (2) a simplified model where ECE score was not included (model 1); and (3) a simplified model where PI-RADS score was not included (model 2). The predictive accuracy of the models was assessed with the receiver operating characteristic-derived area under the curve (AUC). Calibration plots and decision curve analyses were used.

RESULTS

Overall, 149 patients (20%) had LNI. In multivariable logistic regression models, PSA (OR: 1.03; P= 0.001), ISUP grade groups (OR: 1.33; P= 0.001), PCP (OR: 1.01; P= 0.01), and ECE score (ECE 4 vs. 3 OR: 2.99; ECE 5 vs. 3 OR: 6.97; P< 0.001) were associated with higher rates of LNI. The AUC of the Briganti et al. model was 74%. Conversely, the AUC of model 1 vs. model 2 vs. complete model was, respectively, 78% vs. 81% vs. 81%. Simplified model 1 (ECE score only) was then chosen as the best performing model. A nomogram to calculate the individual probability of LNI, based on model 1 was created. Setting our cut-off at 5% we missed only 2.6% of LNI patients.

CONCLUSIONS

We developed a novel nomogram that combines PSA, ISUP grade groups, PCP, and mpMRI-derived ECE score to predict the probability of LNI at final pathology in RARP candidates. The application of a nomogram derived cut-off of 5% allows to avoid a consistent number of ePLND procedures, missing only 2.6% of LNI patients. External validation of our model is needed.

Transperineal systematic biopsies in addition to targeted biopsies are important in the detection of clinically significant prostate cancer

BACKGROUND

This study aimed to determine whether the addition of transperineal systematic biopsies (SB) to targeted biopsies (TB) improved clinically significant prostate cancer (csPC) detection rates without high increase in insignificant prostate cancer detection rates in an Australian population.

METHODS

In this retrospective review, a total of 254 patients who had a Prostate Imaging-Reporting and Data System score between 3 and 5, and a transperineal TB and SB between 2014 and 2019 from two centres were included in this study. The primary outcome of this study was to determine csPC rates on TB and SB. The secondary outcome was a comparison of the Gleason Grade Group between TB and SB. csPC was defined as an International Society of Urological Pathology Gleason Grade Group of 2 or greater.

RESULTS

SB alone detected more csPC overall compared to TB (152/254 (60%) versus 128/254 (51%), respectively). An additional 40 of 254 (16%) csPC cases were diagnosed with the addition of SB. Furthermore, the cost of diagnosing insignificant prostate cancer by SB when TB were negative was an additional 13/254 (5.1%).

CONCLUSION

A combination of TB and SB provides the best outcomes for detecting csPC and is especially warranted for patients with a higher Prostate Imaging-Reporting and Data System score on multiparametric magnetic resonance imaging.

Consecutive transperineal prostatic template biopsies employing cognitive and systematic approach: a single center study

INTRODUCTION

The role of transperineal template biopsy for prostate cancer diagnosis is well established. Pre-biopsy multiparametric magnetic resonance imaging (MRI) is used in most centers for planning of prostate biopsies and staging. Cognitive and software fusion techniques are increasingly getting popular.

METHODS

We retrospectively reviewed patients who underwent transperineal template biopsies from January 2016 till December 2018. This included patients on active surveillance, previous negative transrectal ultrasonography biopsies with persistently raised prostate-specific antigen/abnormal prostate on digital rectal examination and de-novo template biopsies. Two specialist uro-radiologists reported all the scans and the biopsies were performed by one experienced urologist. The cognitive biopsies were performed for PIRADS 3-5 lesions on MRI. Total of 330 patients underwent transperineal template biopsies and cognitive target biopsies were carried out in 75 patients who were included in the study. We evaluated the results as positive/negative cognitive biopsies and also according to the PIRAD scoring. Only the patients with prostate cancer on template biopsy histology were included.

RESULTS

Fifty-seven (76%) of the cognitive biopsies were positive out of total 75.[Table: see text].

CONCLUSIONS

Combined cognitive and systematic biopsies have excellent diagnostic rate especially for PIRAD 4-5 MRI areas.