Systematic review and meta-analysis comparing cognitive vs. image-guided fusion prostate biopsy for the detection of prostate cancer

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.

Optimising prostate biopsies and imaging for the future-a review

Conventionally, transrectal ultrasound guided prostate biopsy (TRUS-Bx) was the main technique used for the diagnosis of prostate cancer since it was first described in 1989 [1]. However, the PROMIS trial showed that this random, nontargeted approach could miss up to 18% of clinically significant cancer (csPCa) [2]. Furthermore, risk of sepsis post TRUS-Bx can be as high as 2.4% [3]. Understanding the demerits of TR-biopsy have led to the introduction of transperineal prostate biopsy (TP-Bx). The incorporation of mpMRI revolutionized prostate cancer diagnostics, allowing visualization of areas likely to harbor csPCa whilst permitting some men to avoid an immediate biopsy. Furthermore, the advent of prostate specific membrane antigen-positron emission tomography (PSMA-PET) is highly promising, because of its role in primary diagnosis of prostate cancer and its higher diagnostic accuracy over conventional imaging in detecting nodal and metastatic lesions. Our narrative review provides an overview on prostate biopsy techniques and an update on prostate imaging, with particular focus on PSMA-PET.

In-bore MRI targeted biopsy. Lights and shadows

Multiparametric Magnetic Resonance Imaging (MpMRI) and MRI-guided biopsy (MRGB) are the diagnostic gold standard in the management of men with suspicious prostate cancer (PCa). There are not enough studies, yet, that compare TRUS-MRGB, COG-TB and IB-MRGB. Despite IB-MRGB could be more accurate in detecting PCa in smaller lesions and a less operator dependent technique, there are still some concerns regarding high resource costs and the chance of missing lesions not visible at MRI or detected by systematic biopsy.

The role of urology and radiology in prostate biopsy: current trends and future perspectives

PURPOSE

Prostate biopsy is central to the accurate histological diagnosis of prostate cancer. In current practice, the biopsy procedure can be performed using a transrectal or transperineal route with different technologies available for targeting of lesions within the prostate. Historically, the biopsy procedure was performed solely by urologists, but with the advent of image-guided techniques, the involvement of radiologists in prostate biopsy has become more common. Herein, we discuss the pros, cons and future considerations regarding their ongoing role.

METHODS

A narrative review regarding the current evidence was completed. PubMed and Cochrane central register of controlled trials were search until January 2024. All study types were of consideration if published after 2000 and an English language translation was available.

RESULTS

There are no published studies that directly compare outcomes of prostate biopsy when performed by a urologist or radiologist. In all published studies regarding the learning curve for prostate biopsy, the procedure was performed by urologists. These studies suggest that the learning curve for prostate biopsy is between 10 and 50 cases to reach proficiency in terms of prostate cancer detection and complications. It is recognised that many urologists are poorly able to accurately interpret multi parametric (mp)-MRI of the prostate. Collaboration between the specialities is of importance with urology offering the advantage of being involved in prior and future care of the patient while radiology has the advantage of being able to expertly interpret preprocedure MRI.

CONCLUSION

There is no evidence to suggest that prostate biopsy should be solely performed by a specific specialty. The most important factor remains knowledge of the relevant anatomy and sufficient volume of cases to develop and maintain skills.

MRI-Ultrasound Fused Approach for Prostate Biopsy-How It Is Performed

The use of MRI-ultrasound image fusion targeted biopsy of the prostate in the face of an elevated serum PSA is now recommended by multiple societies, and results in improved detection of clinically significant cancer and, potentially, decreased detection of indolent disease. This combines the excellent sensitivity of MRI for clinically significant prostate cancer and the real-time biopsy guidance and confirmation of ultrasound. Both transperineal and transrectal approaches can be implemented using cognitive fusion, mechanical fusion with an articulated arm and electromagnetic registration, or pure software registration. The performance has been shown comparable to in-bore MRI biopsy performance. However, a number of factors influence the performance of this technique, including the quality and interpretation of the MRI, the approach used for biopsy, and experience of the practitioner, with most studies showing comparable performance of MRI-ultrasound fusion to in-bore targeted biopsy. Future improvements including artificial intelligence promise to refine the performance of all approaches.

Prostate Cancer Detection Rate of Transperineal Prostate Biopsy: Cognitive vs Software Fusion, A Multicenter Analysis

OBJECTIVE

To compare clinically significant prostate cancer detection with TP-TBx utilizing software vs cognitive fusion. It is established that MRI prior to prostate biopsy improves detection of clinically significant cancer (csPCa, Grade Group ≥2). MRI/US fusion targeted biopsy via a transperineal approach (TP-TBx) is increasing in utilization due to the clean percutaneous approach that greatly reduces postbiopsy infection. However, the comparative effectiveness of formal software fusion over cognitive fusion remains under studied.

MATERIALS AND METHODS

We performed a retrospective multicenter study from June 2020 to July 2022 including age, race, prostate-specific antigen (PSA), prostate volume, PI-RADS, lesion size(s), number of cores sampled, indication (elevated PSA, prior negative, active surveillance) and anesthesia type. Surgeon preference determined use of cognitive (PrecisionPoint) vs software fusion techniques. Multivariable logistic regression determined factors associated with TP-TBx detection of csPCa.

RESULTS

We identified 490 patients (201 cognitive, 289 software fusion) who underwent TP-TBx. Patient age, PSA, number of targets, and PI-RADS were similar (all P > .05). Software fusion TP-TBx had 4 [95% confidence interval (CI) 3-5] more (estimated median difference) systematic cores sampled. csPCa was detected in 44% of all patients. In adjusted analysis, cognitive vs software fusion was similar in detection of csPCa (odds ratio 1.46, 95% CI 0.82-2.58).

CONCLUSION

Cognitive vs software fusion TP-TBx has similar csPCa detection, despite fewer systematic cores taken with cognitive fusion. The expense, additional time requirement, and similar outcomes of software fusion platforms confers higher value to cognitive TP-Bx.

Transitioning from transrectal to transperineal prostate biopsy using a freehand cognitive approach

OBJECTIVES

To report a single-centre experience of a complete transition from transrectal (TR) to transperineal (TP) prostate biopsy under local anaesthesia using a freehand cognitive coaxial approach and without use of antibiotic prophylaxis.

PATIENTS AND METHODS

Analysis was performed of a prospective database of patients undergoing prostate biopsy performed by four surgeons between 1 June 2018 and 31 May 2022. Outcomes of interest were complications, cancer detection rate, inter-operator reliability, and tolerability.

RESULTS

Overall, 1915 patients underwent 2337 separate prostate biopsy sessions. Only 2.4% patients in the TP group received antibiotic prophylaxis, while 100% received antibiotics in the TR group. The complication rate was significantly lower in the TP group compared to the TR group (0.3% vs 5.0%, P < 0.001). In contrast to the TR group, there were no cases of urosepsis or admissions to intensive care in the TP group. The total cancer detection rate by TP biopsy was 70% and the overall pathology detection rate was 88.4%. There was no difference in cancer or pathology detection between operators. A stable level of cancer detection was reached early on for both Prostate Imaging-Reporting and Data System 4 and 5 lesions. All cases performed were performed successfully without need for early termination.

CONCLUSION

Implementing a complete transition from TR to TP biopsy can result in a significant reduction in complications and hospital re-admissions. A cognitive freehand coaxial technique is well tolerated by patients and achieves a high cancer detection rate.

Performance of cognitive vs. image-guided fusion biopsy for detection of overall and clinically significant prostate cancer in a multiethnic population

PURPOSE

Transrectal ultrasound-guided prostate biopsy remains the most used method for the detection of prostate cancer. We recently reported that detection of clinically significant prostate cancer (cs-CaP) using image-guided fusion biopsies (IGFB) varied by race/ethnicity, which calls for further comparison between cognitive fusion biopsy (CFB) and IGFB among non-Hispanic black and Hispanic populations. Therefore, the aim of our study is to compare the rates of detection of cs-CaP and overall CaP by CFB and IGFB in a multiethnic community.

MATERIAL AND METHODS

We performed a retrospective, cross-sectional review of men who underwent MRI-transrectal ultrasound-guided prostate biopsy at our diverse, urban academic medical center. Agreement and discordance between fusion biopsies and systematic biopsies for detection of cs-CaP and overall CaP were determined using Kappa statistics. Univariate and multivariate mixed-effects logistic regression models were used to find associations between fusion modalities and prostate cancer detection.

RESULTS

In total, 710 men underwent fusion prostate biopsies between December 2015 and June 2021. Upon univariate and multivariate logistic regression analysis, there was no significant association between IGFB vs. CFB and risk of overall CaP (OR = 0.66, 95% CI: 0.36-1.21, P = 0.18) or cs-CaP (OR = 0.57, 95% CI: 0.30-1.08, P = 0.09). We found moderate agreement between fusion and systematic biopsies for both CFB (κ = 0.56) and IGFB (κ = 0.52) in cs-CaP.

CONCLUSIONS

CFB and IGFB offer similar detection rates of cs-CaP in a multiethnic population. CFB represents an effective and accessible means of accurately diagnosing prostate cancer.

Comparison in Detection Rate of Clinically Significant Prostate Cancer Between Microultrasound-guided Prostate Biopsy (ExactVu) and Multiparametric Resonance Imaging-guided Prostate Biopsy (Koelis System)

OBJECTIVES

To compare the detection rate of clinically significant prostate cancer (csPC) and prostate cancer (PC) and to find out the diagnostic concordance between microultrasound (mUS), a high-resolution imaging system that can identify suspicious prostate lesions and biopsy them in real time, and multiparametric magnetic resonance imaging (mpMRI)-guided prostate fusion biopsies.

METHODS

A prospective, multicenter, single-blind, single cohort study was conducted involving 80 patients with clinically suspected PC who underwent concomitant mpMRI-guided fusion prostate biopsy (Koelis System) and mUS-guided biopsy (ExactVu System) RESULTS: The detection rate of csPC was slightly higher for image-guided fusion biopsy (21.25% vs 18.75%), but this difference was not statistically significant (P = .453). There was also no significant difference in overall PC diagnosis (50% vs 51.25%, P = .897). The degree of agreement between the 2 diagnostic techniques for the detection of csPC as assessed by Cohen's Kappa concordance index was satisfactory κ ̂ = 0.676. The degree of International Society of Urological Pathology of targeted biopsies obtained from concordant lesions was also represented by satisfactory concordance with a Kappa index of κ ̂ = 0. 696.

CONCLUSION

mUS-guided biopsy is presented as an effective diagnostic method for the diagnosis of csPC compared to image-guided fusion biopsy. No differences are found in the detection rates of csPC and PC between the 2 strategies and satisfactory concordance is found in terms of histopathological findings.

Quantification of Gleason Pattern 4 at MRI-Guided Biopsy to Predict Adverse Pathology at Radical Prostatectomy in Intermediate-Risk Prostate Cancer Patients

BACKGROUND

Data on Gleason pattern 4 (GP4) amount in biopsy tissue is important for prostate cancer (PC) risk assessment. We aim to investigate which GP4 quantification method predicts adverse pathology (AP) at radical prostatectomy (RP) the best in men diagnosed with intermediate-risk (IR) PC at magnetic resonance imaging (MRI)-guided biopsy.

METHODS

We retrospectively included 123 patients diagnosed with IR PC (prostate-specific antigen <20 ng/mL, grade group (GG) 2 or 3, no iT3 on MRI) at MRI-guided biopsy, who underwent RP. Twelve GP4 amount-related parameters were developed, based on GP4 quantification method (absolute, relative to core, or cancer length) and site (overall, targeted, systematic biopsy, or worst specimen). Additionally, we calculated PV×GP4 (prostate volume × GP4 relative to core length in overall biopsy), aiming to represent the total GP4 volume in the prostate. The associations of GP4 with AP (GG ≥ 4, ≥pT3a, or pN1) were investigated.

RESULTS

AP was reported in 39 (31.7%) of patients. GP4 relative to cancer length was not associated with AP. Of the 12 parameters, the highest ROC AUC value was seen for GP4 relative to core length in overall biopsy (0.65). an even higher AUC value was noted for PV × GP4 (0.67), with a negative predictive value of 82.8% at the optimal threshold.

CONCLUSIONS

The lack of an association of GP4 relative to cancer length with AP, contrasted with the better performance of other parameters, indicates directions for future research on PC risk stratification to accurately identify patients who may not require immediate treatment. Incorporating formulas aimed at GP4 volume assessment may lead to obtaining models with the best discrimination ability.

Results of fusion prostate biopsy comparing with cognitive and systematic biopsy

PURPOSE

Our study aims to determine whether there are differences in the degree of detection of prostate cancer (PCa) and CsPCa between fusion prostate biopsy (FPB), cognitive biopsy (PCB), and randomized, systematic biopsy (SB).

METHODS

A retrospective analysis was carried out of 195 patients with suspected PCa at the San Cecilio University Clinical Hospital in Granada who underwent a prostate biopsy between January and December 2021. Patients were divided into three groups: group 1, patients undergoing FPB transperineally with ultrasound BK 3000 (N = 87); group 2, PCB (N = 59) transperineally; and group 3, transrectal SB (N = 49), the latter two, with an ultrasound BK Specto.

RESULTS

We found differences in favor of image-directed biopsies (FPB and PCB) with a percentage of positive biopsies of 52.8% and 50%, respectively, compared to 41.4% with SB, but without these differences being significant. Given the controversy in performing prostate biopsies in PI-RADS 3 lesions reported in the literature, a subanalysis was performed excluding the FPB performed for PI-RADS 3 lesions (PI-RADS 4 and 5 are included), finding significant differences when comparing FPB with PCB and SB (group 1, 64% vs group 2, 45.8%; p = 0.05) (group 1, 64% vs group 3, 42.9%; p = 0.035).

CONCLUSION

With the results obtained in our series, we conclude that the finding of a PI-RADS 3 lesion in mpMRI should not be an absolute criterion to indicate prostate biopsy. On the other hand, for PI-RADS 4 and 5 lesions, FPB is recommended, which in this case turns out to be superior to PCB and SB.

Impact of Ultrasonographic Findings on Cancer Detection Rate during Magnetic Resonance Image/Ultrasonography Fusion-Targeted Prostate Biopsy

PURPOSE

To evaluate the impact of paired transrectal ultrasonography (TRUS) findings of index lesions identified by multiparametric magnetic resonance imaging (mpMRI) on the detection rate of clinically significant prostate cancer (csPCa, Gleason score ≥7) during MRI/US fusion-targeted biopsies.

MATERIALS AND METHODS

From 2019 to 2021, TRUS findings of paired index lesions were prospectively collected from MRI/US cognitive (cTB, n=299) or program-assisted (pTB, n=294) fusion-targeted biopsies. csPCa detection rates according to the presence of a paired hypoechoic lesion (HoEL) and predictive factors for csPCa detection by targeted biopsy were evaluated.

RESULTS

Among 593 patients with visible lesions on upfront mpMRI (Prostate Imaging-Reporting and Data System score ≥3), 288 (48.6%) had paired HoELs on TRUS. The csPCa detection rates in targeted biopsy patients with and without paired HoELs were 56.3% and 10.5% (p<0.001), respectively. Detection rates in patients with and without paired HoELs in the peripheral zone were 65.0% and 14.5%, respectively, and in the transition zone, 37.4% and 8.2%, respectively. In the cTB cohort, a paired HoEL (OR=6.25; p<0.001) was an independent predictive factor for the detection of csPCa in the target core, but not in the pTB cohort (OR=1.92; p=0.107).

CONCLUSIONS

During MRI/US fusion-targeted biopsy, csPCa detection rate was higher in patients with paired HoELs on TRUS than in those without it. After adjustment of the zonal location and mpMRI findings, the presence of paired HoELs is an independent predictive factor for csPCa detection in cTB, but not in pTB. Therefore, paired HoELs improve only the targeting of visually estimated biopsies.

MRI-informed prostate biopsy: What the radiologist should know on quality in biopsy planning and biopsy acquisition

Quality is currently recognized as the pre-requisite for delivering the clinical benefits expected by magnetic resonance imaging (MRI)-informed prostate biopsy (MRI-i-PB) in patients with a suspicion for clinically significant prostate cancer (csPCa). The "quality chain" underlying MRI-i-PB is multidisciplinary in nature, and depends on several factors related to the patient, imaging technique, image interpretation and biopsy procedure. This review aims at making the radiologist aware of biopsy-related factors impacting on MRI-i-PB quality, both in terms of biopsy planning (threshold for biopsy decisions, association with systematic biopsy and number of targeted cores) and biopsy acquisition (biopsy route, targeting technique, and operator's experience). While there is still space for improvement and better standardization of several biopsy-related procedures, current evidence suggests that high-quality MRI-i-PB can be delivered by acquiring and increased the number of biopsy cores targeted to suspicious imaging findings and perilesional area ("focal saturation biopsy"). On the other hand, uncertainty still exists as to whether software-assisted fusion of MRI and transrectal ultrasound images can outperform cognitive fusion strategy. The role for operator's experience and quality assurance/quality control procedures are also discussed.

[Common errors, pitfalls, and management of complications of prostate biopsy : The most common diagnostic and procedural challenges of transrectal fusion prostate biopsy in the initial diagnosis of clinically significant prostate cancer]

BACKGROUND

Transrectal (TR) prostate biopsy is the gold standard in diagnosis of prostate cancer (PC). It requires a precise and safe technique for sample acquisition.

OBJECTIVE

Several approaches will be discussed to avoid overdiagnosis, false-negative results, and complications of the procedure.

MATERIALS AND METHODS

We analyzed national and European guidelines, systematic reviews, meta-analyses, as well as prospective and retrospective studies to describe current trends in indication and performance of biopsies.

RESULTS

Incorporation of risk calculators and magnetic resonance imaging (MRI) into daily routine reduces biopsy rates and results in a more precise diagnosis of clinically significant prostate cancer (csPC). Combination of random- and MRI-fusion guided biopsy-but also extending the radius of sampling by 10 mm beyond the MRI lesion and a transperineal (TP) sampling approach - lead to a higher tumor-detection rate. Bleeding is the most common complication after prostate biopsy and is usually self-limiting. Postbiopsy infection rates can be reduced through TP biopsy.

CONCLUSION

TR MRI-fusion guided biopsy is a widely acknowledged tool in primary diagnostics of csPC. Higher detection rates and safety can be achieved through a TP sampling approach.

Efficacy and safety of the new biopsy strategy combining 6-core systematic and 3-core MRI-targeted biopsy in the detection of prostate cancer: Study protocol for a randomized controlled trial

Background

Recent EAU guideline strongly recommended combined targeted biopsy (TBx) with systematic biopsy (SBx) for biopsy naïve patients with suspected multiparametric magnetic resonance imaging (mpMRI) lesions; However, the clinical goal is to find out how to determine the optimal SBx and TBx cores for biopsy in order to maximize the detection of csPCa and minimize the associated defects. This study aims to assess the efficacy and safety of the new biopsy strategy combining 6-core systematic and 3-core MRI- TBx compared to 12-core systematic and 3-core MRI-TBx strategy.

Methods

This is a single-center, prospectively randomized controlled clinical trial. 280 men meeting inclusion criteria will be recruited and will be randomly allocated to either 6-core systematic plus 3-core MRI-TBx group (Group A) or 12-core systematic plus 3-core MRI-TBx group (Group B). The primary outcome compares the detection rate of PCa and clinically significant prostate cancer(csPCa) between group A and group B. The secondary outcomes compare the participant-reported pain score immediate post biopsy using pain measurement scale; proportion of men with post-biopsy complications and adverse events (Time frame: 7 days post biopsy, 30 days post biopsy); proportion of the men who undergo radical prostatectomy and have cancer upgraded histopathology from the biopsy to the radical prostatectomy.

Results and Discussion

A new biopsy strategy should be developed with the goal of minimizing procedure invasion, our study will provide the results of efficacy and safety of the new biopsy strategy (6-core systematic and 3-core MRI-TBx) in biopsy naïve men with suspicious mpMRI lesion in comparison with 12-core systematic and 3-core MRI-TBx.

Trial registration

Chinese Clinical Trial Registry, ChiCTR2200056437; http://www.chictr.org.cn/edit.aspx?pid=151413&htm=4.

MRI determined prostate volume and the incidence of prostate cancer on MRI-fusion biopsy: a systemic review of reported data for the last 20 years

PURPOSE

Magnetic resonance imaging (MRI) is a precise, systemic and advantageous imaging technique when compared to transrectal ultrasound (TRUS) which is very operator dependent. The negative correlation between prostate volume and the incidence of prostate cancer (PCa) obtained by TRUS biopsy has been well documented in the literature. The purpose of this systemic review is analyzing the reported MRI-fusion study results on prostate biopsies regarding any correlation between prostate volume and the incidence of PCa.

METHODS

After defining the inclusion and exclusion criteria an in-depth review were performed between 01.01.2000 and 02.08.2022 using the PubMed database and applying the "PRISMA" guidelines.

RESULTS

Twelve studies qualified, and all showed an inverse/negative relationship between prostate volume and incidence of PCa. Sample sizes ranged from 33 to 2767 patients in single and multi-institutional studies. All studies showed a statistically significant inverse relationship with a p value < 0.05. The graph summarizing all of studies and using Fisher's method revealed a highly significant combined p level of 0.00001. Additionally, not one single study was found showing the contrary (a positive correlation between prostate size and the incidence of PCa).

CONCLUSION

To our knowledge, this is the first systemic review of reported MRI-Fusion data on the incidence of PCa in correlation with prostate volume. This MRI review confirms previous TRUS-biopsy studies which demonstrated an inverse relationship between prostate volume and the incidence of PCa, and thus further supports the hypothesis that large prostates size may be protective against PCa when compared to smaller prostates.

Prostate biopsy in the era of MRI-targeting: towards a judicious use of additional systematic biopsy

OBJECTIVES

We aimed to develop and compare strategies that help optimize current prostate biopsy practice by identifying patients who may forgo concurrent systematic biopsy (SBx) in favor of MRI-targeted (TBx) alone.

METHODS

Retrospective study on 745 patients who underwent combined MRI-TBx plus SBx. Primary outcome was the upgrade to clinically significant prostate cancer (csPCa; grade group ≥ 2) on SBx versus MRI-TBx. Variables (age, previous biopsy status, Prostate Imaging Reporting and Data System (PI-RADS) score, index lesion size/location, number of lesions, PSA, PSA density, prostate volume) associated with the primary outcome were identified by logistic regression and used for biopsy strategies. Clinical utility was assessed by decision curve analysis (DCA).

RESULTS

SBx detected 47 (6%) additional men with csPCa. The risk of detecting csPCa uniquely on SBx was significantly lower in men with PI-RADS 5 (versus PI-RADS 3: OR 0.30, p = 0.03; versus PI-RADS 4: OR 0.33, p = 0.01), and previous negative biopsy (versus previous positive biopsy: OR 0.40, p = 0.007), and increased with age (per 10 years: OR 1.64, p = 0.016). No significant association was observed for other variables. DCA identified the following strategies as most useful: (a) avoid SBx in men with PI-RADS 5 and (b) additionally in those with previous negative biopsy, resulting in avoiding SBx in 201 (27%) and 429 (58%), while missing csPCa in 5 (1%) and 15 (2%) patients, respectively.

CONCLUSION

Not all men benefit equally from the combination of SBx and MRI-TBx. SBx avoidance in men with PI-RADS 5 and/or previous negative biopsy may reduce the risk of excess biopsies with a low risk of missing csPCa.

KEY POINTS

• In men undergoing MRI-targeted biopsy, the risk of detecting clinically significant prostate cancer (csPCa) only on additional systematic biopsy (SBx) decreased in men with PI-RADS 5, previous negative biopsy, and younger age. • Using these variables may help select men who could avoid the risk of excess SBx. • If missing csPCa in 5% was acceptable, forgoing SBx in men with PI-RADS 5 and/or previous negative biopsy enabled the highest net reduction in SBx.

Selecting patients for magnetic resonance imaging cognitive versus ultrasound fusion biopsy of the prostate: A within-patient comparison

Objectives

To compare overall agreement between magnetic resonance imaging (MRI)-ultrasound (US) fusion biopsy (FB) and MRI cognitive fusion biopsy (CB) of the prostate and determine which factors affect agreement for prostate cancer (PCa) who underwent both modalities in a prospective within-patient protocol.

Patients and Methods

From August 2017 to January 2021, patients with at least one Prostate Imaging Reporting & Data System (PI-RADS) 3 or higher lesion on multiparametric MRI underwent transrectal FB and CB in a prospective within-patient protocol. CB was performed for each region of interest (ROI), followed by FB, followed by standard 12 core biopsy. Patients who were not on active surveillance were analysed. The primary endpoint was agreement for any PCa detection. McNemar's test and kappa statistic were used to analyse agreement. Chi-square test, Fisher's exact test and Wilcoxon rank sum test were used to analyse disagreement across clinical and MRI spatial variables. A multivariable generalized mixed-effect model was used to compare the interaction between select variables and fusion modality. Statistics were performed using SAS and R.

Results

Ninety patients and 98 lesions were included in the analysis. There was moderate agreement between FB and CB (k = 0.715). McNemar's test was insignificant (p = 0.285). Anterior location was the only variable associated with a significant variation in agreement, which was 70% for anterior lesions versus 89.7% for non-anterior lesions (p = 0.035). Discordance did not vary significantly across other variables. In a mixed-effect model, the interaction between anterior location and use of FB was insignificant (p = 0.411).

Conclusion

In a within-patient protocol of patients not on active surveillance, FB and CB performed similarly for PCa detection and with moderate agreement. Anterior location was associated with significantly higher disagreement, whereas other patient and lesion characteristics were not. Additional studies are needed to determine optimal biopsy technique for sampling anterior ROI.

Canadian Association of Radiologists Prostate MRI White Paper

Prostate cancer is the most common malignancy and the third most common cause of death in Canadian men. In light of evolving diagnostic pathways for prostate cancer and the increased use of MRI, which now includes its use in men prior to biopsy, the Canadian Association of Radiologists established a Prostate MRI Working Group to produce a white paper to provide recommendations on establishing and maintaining a Prostate MRI Programme in the context of the Canadian healthcare system. The recommendations, which are based on available scientific evidence and/or expert consensus, are intended to maintain quality in image acquisition, interpretation, reporting and targeted biopsy to ensure optimal patient care. The paper covers technique, reporting, quality assurance and targeted biopsy considerations and includes appendices detailing suggested reporting templates, quality assessment tools and sample image acquisition protocols relevant to the Canadian healthcare context.

mpMRI-US Fusion-Guided Targeted Cryotherapy in Patients with Primary Localized Prostate Cancer: A Prospective Analysis of Oncological and Functional Outcomes

Simple Summary

Targeted cryotherapy is an emerging treatment for prostate cancer (PCa). mpMRI is a powerful tool for image fusion techniques that deliver incremental precision in diagnostic and treatment of PCa. Fusion targeted cryotherapy (FTC) arises from the simultaneous application of both these procedures. Recurrence is a concern after any type of PCa treatment, especially after targeted treatments. In this article we investigate the recurrence rate after FTC and the role of Prostate-Specific Antigen (PSA) as a predictor of recurrences. Our research provides new evidence on the feasibility of FCT by providing new insights on patient management.

Abstract

Targeted therapy (TT) for prostate cancer (PCa) aims to ablate the malignant lesion with an adequate margin of safety in order to obtain similar oncological outcomes, but with less toxicity than radical treatments. The main aim of this study was to evaluate the recurrence rate (RR) in patients with primary localized PCa undergoing mpMRI/US fusion targeted cryotherapy (FTC). A secondary objective was to evaluate prostate-specific antigen (PSA) as a predictor of recurrences. We designed a prospective single-center single-cohort study. Patients with primary localized PCa, mono or multifocal lesions, PSA ≤ 15 ng/mL, and a Gleason score (GS) ≤ 4 + 3 undergoing FTC were enrolled. RR was chosen as the primary outcome. Recurrence was defined as the presence of clinically significant prostate cancer in the treated areas. PSA values measured at different times were tested as predictors of recurrence. Continuous variables were assessed with the Bayesian t-test and categorical assessments with the chix-squared test. Univariate and logistic regression assessment were used for predictions. A total of 75 cases were included in the study. Ten subjects developed a recurrence (RR: 15.2%), while fifty-six (84.8%) patients showed a recurrence-free status. A %PSA drop of 31.5% during the first 12 months after treatment predicted a recurrence with a sensitivity of 53.8% and a specificity of 79.2%. A PSA drop of 55.3% 12 months after treatment predicted a recurrence with a sensitivity of 91.7% and a specificity of 51.9%. FTC for primary localized PCa seems to be associated with a low but not negligible percentage of recurrences. Serum PSA levels may have a role indicating RR.

Fusion versus cognitive MRI-guided prostate biopsies in diagnosing clinically significant prostate cancer

Objective:

This study assesses whether fusion or cognitive magnetic resonance imaging (MRI)-guided prostate targeted and systematic transperineal biopsies (TPB) increase detection of clinically significant prostate cancer (csPCa).

Materials and Methods:

A retrospective analysis was completed of patients (2018–2020) undergoing 3-Tesla multiparametric prostate MRI informing targeted (either cognitive or MIM software fusion approach) and systematic TPB. ISUP (International Society of Urological Pathology) grade group ⩾ 2 was considered csPCa.

Results:

A total of 355 cases from 4 urologists were included; 131 were fusion and 224 were cognitive MRI-guided biopsies. Of all csPCa found, 86.8% ( n = 171) of cases were confirmed to be at the MRI-indicated location and 11.6% were found as part of active surveillance. In all, 45.0% of the fusion group were found to have csPCa, compared to 62.05% ( n = 139) in the cognitive group ( p = 0.002). csPCa detection rates varied between urologists (41% to 78%, p < 0.001), so a subgroup analysis was performed on Urologist A; 45.0% of fusion and 41.3% of cognitive biopsies had csPCa ( p = 0.644). Multinomial logistic regression analysis showed that biopsy type, being on active surveillance, number of biopsy cores, iPSA (initial Prostate Specific Antigen) value or PIRADS (Prostate Imaging-Reporting and Data System) score made no significant difference in whether csPCa was found.

Conclusion:

Cognitive and fusion targeting had similar csPCa detection rates. Further prospective studies would be beneficial to validate these findings.

Level of evidence:

2b (according to Oxford Centre for Evidence-Based Medicine)

The challenge of prostate biopsy guidance in the era of mpMRI detected lesion: ultrasound-guided versus in-bore biopsy

The current recommendation in patients with a clinical suspicion for prostate cancer is to perform systematic biopsies extended with targeted biopsies, depending on mpMRI results. Following a positive mpMRI [i.e. Prostate Imaging Reporting and Data System (PI-RADS) ≥3], three targeted biopsy approaches can be performed: visual registration of the MRI images with real-time ultrasound imaging; software-assisted fusion of the MRI images and real-time ultrasound images, and in-bore biopsy within the MR scanner. This collaborative review discusses the advantages and disadvantages of each targeting approach and elaborates on future developments. Cancer detection rates seem to mostly depend on practitioner experience and selection criteria (biopsy naïve, previous negative biopsy, prostate-specific antigen (PSA) selection criteria, presence of a lesion on MRI), and to a lesser extent dependent on biopsy technique. There is no clear consensus on the optimal targeting approach. The choice of technique depends on local experience and availability of equipment, individual patient characteristics, and onsite cost-benefit analysis. Innovations in imaging techniques and software-based algorithms may lead to further improvements in this field.

Minimally Invasive Procedures in the Diagnosis and Treatment of Localized Prostate Cancer: an Interventional Radiologist's Perspective

PURPOSE OF REVIEW

Minimal invasive procedures, including targeted biopsy (TB) and focal therapy (FT), are increasingly used in diagnosis and treatment of localized prostate cancer. Here, we review the current role of these procedures, from a perspective of an interventional radiologist.

RECENT FINDINGS

TB is an established part of current guidelines for diagnosis of PCa. Several modalities of FT are gaining prevalence in recent years, as a tissue-preserving alternative for definitive treatment of localized PCa. FT is currently at early research stages, offered to selected patients in clinical trials settings. TB and FT are minimally invasive procedures used by multidisciplinary teams for diagnosis and treatment of localized PCa.

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.

How to Improve TRUS-Guided Target Biopsy following Prostate MRI

TRUS is a basic imaging modality when radiologists or urologists perform cognitive fusion or image fusion biopsy. This modality plays the role of the background images to add to an operator's cognitive function or MRI images. Operators need to know how to make TRUS protocols for lesion detection or targeting. Tumor location, size, and shape on TRUS are different from those on MRI because the scan axis is different. TRUS findings of peripheral or transition tumors are not well known to radiologists and urologists. Moreover, it remains unclear if systematic biopsy is necessary after a tumor is targeted. The purpose of this review is to introduce new TRUS protocols, new imaging features, new biopsy techniques, and to assess the necessity of systematic biopsy for improving biopsy outcomes.

Systematic biopsy should not be omitted in the era of combined magnetic resonance imaging/ultrasound fusion-guided biopsies of the prostate

PURPOSE

To evaluate prostate cancer detection rates with classical trans-rectal ultrasound-guided systematic 10-core biopsies (SB), targeted biopsies (TB) guided by magnetic resonance (MR)/US fusion imaging and their combination in biopsy-naïve and patients with previously negative prostate biopsies. We compared pathology results after radical prostatectomy with biopsy findings.

METHODS

Consecutive patients with prostate imaging-reporting and data system lesions grade ≥ 3 submitted to MRI/US-guided TB and subsequent standard 10-core SB between December 2015 and June 2019 were analyzed.

RESULTS

Detection rate (TB- or SB-positive) in 563 included patients (192 naïve, 371 with previous biopsies) was 56.7% (67.7% for the first, 50.9% for repeated biopsies). With TB (disregarding SB), the rates were 41.4%, 52.1% and 35.8%, respectively. With SB (disregarding TB), the rates were 49.1%, 63.0% and 41.8%, respectively. Eventually, 118 patients underwent surgery and clinically significant cancer was found in 111 (94.1%) specimens. Of those, 23 (20.7%) would have been missed had we relied upon a negative TB and 14 (12.6%) would have been missed had we relied upon a negative SB, disregarding a positive finding on the alternative biopsy template.

CONCLUSION

SB should not be omitted since TB and SB combination have higher detection rate of clinically relevant prostate cancer than either procedure alone.

Usability and diagnostic accuracy of different MRI/ultrasound-guided fusion biopsy systems for the detection of clinically significant and insignificant prostate cancer: a prospective cohort study

PURPOSE

To explore the usability and diagnostic accuracy for prostate cancer of three multiparametric magnetic resonance imaging (mpMRI)/transrectal ultrasound (TRUS)-guided fusion biopsy systems operated by the same urologists.

METHODS

We performed a prospective, observational study including patients that underwent prostate biopsy due to a visible lesion in mpMRI (PI-RADS ≥ 3). We consecutively assessed two platforms with a rigid image registration (BioJet, D&K Technologies and UroNav, Invivo Corporation) and one with an elastic registration (Trinity, KOELIS). Four urologists evaluated each fusion system in terms of usability based on the System Usability Scale and diagnostic accuracy based on the detection of prostate cancer.

RESULTS

We enrolled 60 consecutive patients that received mpMRI/TRUS-guided prostate biopsy with the BioJet (n = 20), UroNav (n = 20) or Trinity (n = 20) fusion system. Comparing the rigid with the elastic registration systems, the rigid registration systems were more user-friendly compared to the elastic registration systems (p = 0.012). Similarly, the prostate biopsy with the rigid registration systems had a shorter duration compared to the elastic registration system (p < 0.001). Overall, 40 cases of prostate cancer were detected. Of them, both the BioJet and UroNav fusion systems detected 13 prostate cancer cases, while the Trinity detected 14. No significant differences were demonstrated among the three fusion biopsy systems in terms of highest ISUP Grade Group (p > 0.99).

CONCLUSIONS

Rigid fusion biopsy systems are easier to use and provide shorter operative time compared to elastic systems, while both types of platforms display similar detection rates for prostate cancer. Still, further high-quality, long-term results are mandatory.

New TRUS Techniques and Imaging Features of PI-RADS 4 or 5: Influence on Tumor Targeting

Purpose

To determine if the new transrectal ultrasound (TRUS) techniques and imaging features contribute to targeting Prostate Imaging and Reporting and Data System (PI-RADS) 4 or 5.

Materials and Methods

Between December 2018 and February 2020, 115 men underwent cognitive biopsy by radiologist A, who was familiar with the new TRUS findings and biopsy techniques. During the same period, 179 men underwent magnetic resonance imaging–TRUS image fusion or cognitive biopsy by radiologist B, who was unfamiliar with the new biopsy techniques. Prior to biopsy, both radiologists knew MRI findings such as the location, size, and shape of PI-RADS 4 or 5. We recorded how many target biopsies were performed without systematic biopsy and how many of these detected higher Gleason score (GS) than those detected by systematic biopsy. The numbers of biopsy cores were also obtained. Fisher Exact or Mann–Whitney test was used for statistical analysis.

Results

For PI-RADS 4, target biopsy alone was performed in 0% (0/84) by radiologist A and 0.8% (1/127) by radiologist B (p>0.9999). Target biopsy yielded higher GSs in 57.7% (30/52) by radiologist A and 29.5% (23/78) by radiologist B (p = 0.0019). For PI-RADS 5, target biopsy alone was performed in 29.0% (9/31) by radiologist A and 1.9% (1/52) by radiologist B (p = 0.0004). Target biopsy yielded higher GSs in 50.0% (14/28) by radiologist A and 18.2% (8/44) by radiologist B (p = 0.0079). Radiologist A sampled fewer biopsy cores than radiologist B (p = 0.0008 and 0.0023 for PI-RADS 4 and 5), respectively.

Conclusions

PI-RADS 4 or 5 can be more precisely targeted if the new TRUS biopsy techniques are applied.

Developing a coordinate-based strategy to support cognitive targeted prostate biopsies and correlative spatial-histopathological outcome analysis

Lack of investment for magnetic resonance (MR) fusion systems is an obstacle to deliver targeted prostate biopsies within the prostate cancer diagnostic pathway. We developed a coordinate-based method to support cognitive targeted prostate biopsies and then performed an audit on cancer detection and the location of lesions. In each patient, the prostate is considered as two separate hemiprostates, and each hemiprostate is divided into 4 × 4 × 4 units. Each unit is therefore defined by a three-dimensional coordinate. We prospectively applied our coordinates approach to target 106 prostatic lesions in 93 men. Among 45 (of 106; 42.5%) lesions positive for cancer, 27 lesions (60.0%) harbored clinically significant disease. PSA density was significantly higher in patients with proven cancer (median: 0.264 ng ml-2) when compared to the noncancer group (median: 0.145 ng ml-2; P = 0.003, Wilcoxon rank-sum test). Lesions with Prostate Imaging-Reporting and Data System (PIRADS) score of 5 were found to have a cancer incidence of 65.2%, while PIRADS 4 and 3 lesions have a lower risk of cancer detection, as expected, at 37.3% and 31.3%, respectively. The probability of a lesion being cancerous in our series significantly decreases as we go from the "apex-to-base" dimension (odds ratio [OR]: 2.62, 95% confidence interval [CI]: 1.55-4.44, P = 0.00034). Our analysis also indicates that the probability of cancer decreases as the prostate volume increases (OR: 1.03, 95% CI: 1.01-1.05, P = 0.00327). Based on this feasibility study, the use of coordinates to guide cognitive targeted prostate biopsies warrants future validation study in additional centers.

Comparative Effectiveness of Techniques in Targeted Prostate Biopsy

Simple Summary

Prostate cancer is one of the most common cancers in men. Traditionally, prostate cancer is diagnosed via transrectal ultrasound-guided prostate biopsy, using a systematic random template. Using multiparametric magnetic resonance imaging, lesions suspicious for prostate cancer can be identified, and subsequently targeted on biopsy, allowing for increased diagnostic accuracy. This article reviewed the current literature surrounding various types of targeted biopsy, such as transperineal biopsy, allowing for comparison not only between targeted biopsy and systematic biopsy, but also between different varieties of targeted biopsy.

Abstract

In this review, we evaluated literature regarding different modalities for multiparametric magnetic resonance imaging (mpMRI) and mpMRI-targeted biopsy (TB) for the detection of prostate cancer (PCa). We identified studies evaluating systematic biopsy (SB) and TB in the same patient, thereby allowing each patient to serve as their own control. Although the evidence supports the accuracy of TB, there is still a proportion of clinically significant PCa (csPCa) that is detected only in SB, indicating the importance of maintaining SB in the diagnostic pathway, albeit with additional cost and morbidity. There is a growing subset of data which supports the role of TB alone, which may allow for increased efficiency and decreased complications. We also compared the literature on transrectal (TR) vs. transperineal (TP) TB. Although further high-level evidence is necessary, current evidence supports similar csPCa detection rate for both approaches. We also evaluated various TB techniques such as cognitive fusion biopsy (COG-TB) and in-bore biopsy (IB-TB). COG-TB has comparable detection rates to software fusion, but is operator-dependent and may have reduced accuracy for smaller lesions. IB-TB may allow for greater precision as lesions are directly targeted; however, this is costly and time-consuming, and does not account for MRI-invisible lesions.