Optimizing the Number of Cores Targeted During Prostate Magnetic Resonance Imaging Fusion Target Biopsy

How Many Cores Should Be Collected per Region of Interest in Fusion Targeted Prostate Biopsy? A Retrospective Single Institution Statistical Simulation

OBJECTIVE

To determine how many cores should be collected per region of interest (ROI) in magnetic resonance imaging-guided fusion prostate biopsy. Magnetic resonance imaging-guided targeted prostate biopsy has led to improved detection of clinically significant prostate cancer (csPC); however, data is limited regarding the optimal number of biopsy cores that should be taken. An ideal number of cores maximizes clinically significant cancer detection while minimizing cost, discomfort, and procedure time.

METHODS

Patients receiving targeted prostate biopsy (4 cores per ROI) combined with systematic 12-core prostate at our institution between January 2017 and June 2022 were retrospectively identified. Statistical simulation was used to model scenarios in which 1, 2, 3, or 4 cores were taken from the ROI, and the rate of grade group ≥2 prostate cancer (csPC) detection was determined for targeted and combined targeted plus systematic biopsy.

RESULTS

483 patients were identified. Transrectal (96%) and transperineal (4%) biopsies were included. For targeted biopsy, csPC was present in 21% (1 core), 26% (2 cores; P = .048), 29% (3 cores; P = .002), and 31% (4 cores; P < .001) of cases. For combined biopsy, csPC was present in 33% (1 core), 35% (2 cores; P = .4), 37% (3 cores; P = .2), and 38% (4 cores; P = .12) of cases.

CONCLUSION

If targeted biopsy is performed without systematic biopsy, 2 or more cores is superior to 1 core for detecting csPC. This effect is mitigated when targeted and systematic biopsy are combined.

Enhancing Prostate Cancer Diagnosis: Artificial Intelligence-Driven Virtual Biopsy for Optimal Magnetic Resonance Imaging-Targeted Biopsy Approach and Gleason Grading Strategy

An optimal approach to magnetic resonance imaging fusion targeted prostate biopsy (PBx) remains unclear (number of cores, intercore distance, Gleason grading [GG] principle). The aim of this study was to develop a precise pixel-wise segmentation diagnostic artificial intelligence (AI) algorithm for tumor detection and GG as well as an algorithm for virtual prostate biopsy that are used together to systematically investigate and find an optimal approach to targeted PBx. Pixel-wise AI algorithms for tumor detection and GG were developed using a high-quality, manually annotated data set (slides n = 442) after fast-track annotation transfer into segmentation style. To this end, a virtual biopsy algorithm was developed that can perform random biopsies from tumor regions in whole-mount whole-slide images with predefined parameters. A cohort of 115 radical prostatectomy (RP) patient cases with clinically significant, magnetic resonance imaging-visible tumors (n = 121) was used for systematic studies of the optimal biopsy approach. Three expert genitourinary (GU) pathologists (Y.T., A.P., A.Q.) participated in the validation. The tumor detection algorithm (aware version sensitivity/specificity 0.99/0.90, balanced version 0.97/0.97) and GG algorithm (quadratic kappa range vs pathologists 0.77-0.78) perform on par with expert GU pathologists. In total, 65,340 virtual biopsies were performed to study different biopsy approaches with the following results: (1) 4 biopsy cores is the optimal number for a targeted PBx, (2) cumulative GG strategy is superior to using maximal Gleason score for single cores, (3) controlling for minimal intercore distance does not improve the predictive accuracy for the RP Gleason score, (4) using tertiary Gleason pattern principle (for AI tool) in cumulative GG strategy might allow better predictions of final RP Gleason score. The AI algorithm (based on cumulative GG strategy) predicted the RP Gleason score of the tumor better than 2 of the 3 expert GU pathologists. In this study, using an original approach of virtual prostate biopsy on the real cohort of patient cases, we find the optimal approach to the biopsy procedure and the subsequent GG of a targeted PBx. We publicly release 2 large data sets with associated expert pathologists' GG and our virtual biopsy algorithm.

A new parameter to increase the predictive value of multiparametric prostate magnetic resonance imaging for clinically significant prostate cancer in targeted biopsies: lesion density

Aim

To investigate the predictive value of lesion length in multiparametric prostate magnetic resonance imaging with respect to prostate volume for clinically significant prostate cancer diagnosis in targeted biopsies.

Materials and methods

The data of biopsy-naïve patients in the Turkish Urooncology Association Prostate Cancer Database who underwent targeted prostate biopsies were included in this study. Lesion density is calculated as the ratio of lesion length (mm) in MR to prostate volume (cc). The biopsy results were divided into either clinically significant or insignificant cancer and benign groups. The difference in parameters between groups is evaluated by multivariable analysis to determine independent risk factors for clinically significant prostate cancer diagnosis.

Results

A total of 590 lesion biopsies were included in the study. In univariable analysis, prostate-specific antigen (PSA), PSA density, number of cores taken, lesion length, lesion density, patient age, and digital rectal examination findings were found to be different at a statistically significant level between groups (P values, respectively: 0.001, <0.001, <0.001, <0.001, <0.001, 0.012, 0.001). Subgroup analysis demonstrated that the lesion density was still significantly different between groups for all Prostate Imaging - Reporting and Data System (PI-RADS) 3, 4, and 5 subgroups (P values, respectively: 0.001, <0.001, <0.001). The multivariable analysis demonstrated that lesion density, along with the number of cores taken and the PI-RADS score of the lesion is an independent risk factor for predicting clinically significant prostate cancer, with the highest odds ratio among all parameters (OR: 27.31 [CI: 7.9-94.0]).

Conclusion

This study demonstrated that lesion size with respect to prostate volume is an important independent risk factor for the prediction of clinically significant prostate cancer in the lesion-targeted biopsy. Combined with the PI-RADS score and parameters like digital rectal examination (DRE) findings and PSA density may further increase predictive power and help clinicians decide whether to perform a biopsy in low-risk patients or perform a re-biopsy for high-risk patients subsequent to an initial negative biopsy.

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.

Sextant Systematic Biopsy Versus Extended 12-Core Systematic Biopsy in Combined Biopsy for Prostate Cancer

BACKGROUND

This study assessed the comparative effectiveness of sextant and extended 12-core systematic biopsy within combined biopsy for the detection of prostate cancer.

METHODS

Patients who underwent combined biopsy targeting lesions with a Prostate Imaging Reporting and Data System (PI-RADS) score of 3-5 were assessed. Two specialists performed all combined cognitive biopsies. Both specialists performed target biopsies with five or more cores. One performed sextant systematic biopsies, and the other performed extended 12-core systematic biopsies. A total of 550 patients were analyzed.

RESULTS

Cases requiring systematic biopsy in combined biopsy exhibited a significant association with age ≥ 65 years (odds ratio [OR], 2.32; 95% confidence interval [CI], 1.25-4.32; P = 0.008), PI-RADS score (OR, 2.32; 95% CI, 1.25-4.32; P = 0.008), and the number of systematic biopsy cores (OR, 3.69; 95% CI, 2.11-6.44; P < 0.001). In patients with an index lesion of PI-RADS 4, an extended 12-core systematic biopsy was required (target-negative/systematic-positive or a greater Gleason score in the systematic biopsy than in the targeted biopsy) (P < 0.001).

CONCLUSION

During combined biopsy for prostate cancer in patients with PI-RADS 3 or 5, sextant systematic biopsy should be recommended over extended 12-core systematic biopsy when an effective targeted biopsy is performed.

Targeted Prostate Biopsies-What the Radiologist Needs to Know

The emergence of multiparametric MR imaging has enabled a more reliable targeted approach to diagnosis of prostate cancer. Targeted biopsies are central to the MR imaging-dependent pathway to prostate cancer diagnosis and potentially improve the detection of clinically significant prostate cancers. In a targeted biopsy, tissue samples are obtained from suspicious regions identified on a prebiopsy diagnostic MR imaging. This article describes and compares principles, advantages, and disadvantages of the different strategies available for targeting an MR imaging-visible suspicious lesion.

MRI-targeted biopsy cores from prostate index lesions: assessment and prediction of the number needed

BACKGROUND

Magnetic resonance imaging (MRI) is used to detect the prostate index lesion before targeted biopsy. However, the number of biopsy cores that should be obtained from the index lesion is unclear. The aim of this study is to analyze how many MRI-targeted biopsy cores are needed to establish the most relevant histopathologic diagnosis of the index lesion and to build a prediction model.

METHODS

We retrospectively included 451 patients who underwent 10-core systematic prostate biopsy and MRI-targeted biopsy with sampling of at least three cores from the index lesion. A total of 1587 biopsy cores were analyzed. The core sampling sequence was recorded, and the first biopsy core detecting the most relevant histopathologic diagnosis was identified. In a subgroup of 261 patients in whom exactly three MRI-targeted biopsy cores were obtained from the index lesion, we generated a prediction model. A nonparametric Bayes classifier was trained using the PI-RADS score, prostate-specific antigen (PSA) density, lesion size, zone, and location as covariates.

RESULTS

The most relevant histopathologic diagnosis of the index lesion was detected by the first biopsy core in 331 cases (73%), by the second in 66 cases (15%), and by the third in 39 cases (9%), by the fourth in 13 cases (3%), and by the fifth in two cases (<1%). The Bayes classifier correctly predicted which biopsy core yielded the most relevant histopathologic diagnosis in 79% of the subjects. PI-RADS score, PSA density, lesion size, zone, and location did not independently influence the prediction model.

CONCLUSION

The most relevant histopathologic diagnosis of the index lesion was made on the basis of three MRI-targeted biopsy cores in 97% of patients. Our classifier can help in predicting the first MRI-targeted biopsy core revealing the most relevant histopathologic diagnosis; however, at least three MRI-targeted biopsy cores should be obtained regardless of the preinterventionally assessed covariates.

Prostate Biopsy in the Case of PIRADS 5-Is Systematic Biopsy Mandatory?

Combining systematic biopsy (SB) with targeted biopsy (TB) in the case of a positive result from multiparametric magnetic resonance imaging (mpMRI) is a matter of debate. The Prostate Imaging Reporting and Data System (PIRADS) score of 5 indicates the highest probability of clinically significant prostate cancer (csPC) detection in TB. Potentially, omitting SB in the case of PIRADS 5 may have a marginal impact on the csPC detection rate. The aim of this study was to determine whether SB can be avoided in the case of PIRADS 5 and to identify potential factors allowing for performing TB only. This cohort study involved n = 225 patients with PIRADS 5 on mpMRI (PIRADS 2.0/2.1) who underwent transperineal or transrectal combined biopsy (CB). CsPC was diagnosed in 51.6% (n = 116/225) of cases. TB and SB resulted in the detection of csPC in 48% (n = 108/225) and 20.4% (n = 46/225) of cases, respectively (TB vs. SB, p < 0.001). When the TB was positive, SB detected csPC in n = 38 of the cases (38/108 = 35%). SB added to TB significantly improved csPC detection in 6.9% of cases in absolute terms (n = 8/116) (TB vs. CB, p = 0.008). The multivariate regression model proved that the significant predictors of csPC detection via SB were the densities of the prostate-specific antigen-PSAD > 0.17 ng/mL2 (OR = 4.038, 95%CI: 1.568-10.398); primary biopsy setting (OR = 2.818, 95%CI: 1.334-5.952); and abnormal digital rectal examination (DRE) (OR = 2.746, 95%CI: 1.328-5.678). In a primary biopsy setting (n = 103), SB detected 10% (n = 6/60) of the additional cases of csPC (p = 0.031), while in a repeat biopsy setting (n = 122), SB detected 3.5% (n = 2/56) of the additional cases of csPC (p = 0.5). In the case of PSAD > 0.17 ng/mL2 (n = 151), SB detected 7.4% (n = 7/95) of additional cases of csPC (p = 0.016), while in the case of PSAD < 0.17 ng/mL2 (n = 74), SB detected 4.8% (n = 1/21) of the additional cases of csPC (p = 1.0). The omission of SB had an impact on the csPC diagnosis rate in patients with PIRADS 5 score lesions. Patients who have already undergone prostate biopsy and those with low PSAD are at a lower risk of missing csPC when SB is avoided. However, performing TB only may result in missing other csPC foci located outside the index lesion, which can alter treatment decisions.

The Impact of Prostate Volume on the Prostate Imaging and Reporting Data System (PI-RADS) in a Real-World Setting

Multiparametric magnetic resonance imaging (mpMRI) has emerged as a new cornerstone in the diagnostic pathway of prostate cancer. However, mpMRI is not devoid of factors influencing its detection rate of clinically significant prostate cancer (csPCa). Amongst others, prostate volume has been demonstrated to influence the detection rates of csPCa. Particularly, increasing volume has been linked to a reduced cancer detection rate. However, information about the linkage between PI-RADS, prostate volume and detection rate is relatively sparse. Therefore, the current study aims to assess the association between prostate volume, PI-RADS score and detection rate of csP-Ca, representing daily practice and contemporary mpMRI expertise. Thus, 1039 consecutive patients with 1151 PI-RADS targets, who underwent mpMRI-guided prostate biopsy at our tertiary referral center, were included. Prior mpMRI had been assessed by a plethora of 111 radiology offices, including academic centers and private practices. mpMRI was not secondarily reviewed in house before biopsy. mpMRI-targeted biopsy was performed by a small group of a total of ten urologists, who had performed at least 100 previous biopsies. Using ROC analysis, we defined cut-off values of prostate volume for each PI-RADS score, where the detection rate drops significantly. For PI-RADS 4 lesions, we found a volume > 61.5 ccm significantly reduced the cancer detection rate (OR 0.24; 95% CI 0.16-0.38; p < 0.001). For PI-RADS 5 lesions, we found a volume > 51.5 ccm to significantly reduce the cancer detection rate (OR 0.39; 95% CI 0.25-0.62; p < 0.001). For PI-RADS 3 lesions, none of the evaluated clinical parameters had a significant impact on the detection rate of csPCa. In conclusion, we show that enlarged prostate volume represents a major limitation in the daily practice of mpMRI-targeted biopsy. This study is the first to define exact cut-off values of prostate volume to significantly impair the validity of PI-RADS assessed in a real-world setting. Therefore, the results of mpMRI-targeted biopsy should be interpreted carefully, especially in patients with prostate volumes above our defined thresholds.

Optimizing multiparametric magnetic resonance imaging-targeted biopsy and detection of clinically significant prostate cancer: the role of core number and location

PURPOSE

There is currently no consensus regarding the optimal number of multiparametric magnetic resonance imaging (MRI)-targeted biopsy (TB) cores and their spatial distribution within the MRI lesion. We aim to determine the number of TB cores and location needed to adequately detect csPCa.

METHODS

We conducted a retrospective cohort study of 505 consecutive patients undergoing TB for positive MRI lesions defined by a PI-RADS score ≥ 3 between June 2016 and January 2022. Cores chronology and locations were prospectively recorded. The co-primary outcomes were the first core to detect clinically significant prostate cancer (csPCa) and the first highest ISUP grade group. The incremental benefit of each additional core was evaluated. Analysis was then performed by distinguishing central (cTB) and peripheral (pTB) within the MRI lesion.

RESULTS

Overall, csPCa was detected in 37% of patients. To reach a csPCa detection rate of 95%, a 3-core strategy was required, except for patients with PI-RADS 5 lesions and those with PSA density ≥ 0.2 ng/ml/cc who benefited from a fourth TB core. At multivariable analysis, only a PSA density ≥ 0.2 ng/ml/cc was an independent predictive factor of having the highest ISUP grade group on the fourth TB cores (p = 0.03). No significant difference in the cancer detection rate was found between cTB and pTB (p = 0.9). Omitting pTB would miss 18% of all csPCa.

CONCLUSION

A 3-core strategy should be considered for TB to optimize csPCa detection with additional cores needed for PI-RADS 5 lesions and high PSA density. Biopsy cores from both central and peripheral zones are required.

Systematic Review and Meta-Analysis of Free-Hand and Fixed-Arm Spatial Tracking Methodologies in Software-Guided MRI-TRUS Fusion Prostate Biopsy Platforms

OBJECTIVE

To evaluate the cancer detection rate (CDR) between the 2 dominant spatial tracking methodologies in software-guided MRI-transrectal ultrasound fusion prostate biopsy (SGF-Bx) platforms: fixed-arm and free-hand.

METHODS

We conducted a systematic review and meta-analysis on published primary analyses of prospective trials and cohort studies that enrolled biopsy-naïve patients for SFG-Bx. Inclusion criteria included the use of the Prostate Imaging Reporting & Data System (PI-RADS) v2.0 or later and the targeting of lesions graded as PI-RADS 3 or higher. Random effects models were used to assess the overall prostate cancer (PCa) CDR and the clinically significant prostate cancer (csPCa) CDR for both platforms. csPCa was standardized to a definition of Gleason Grade Group 2 or higher when possible. Subgroup analysis was performed by stratifying studies into the average number of cores taken per lesion.

RESULTS

The PCa CDR was 0.674 for free-hand systems and 0.681 for fixed-arm systems. The csPCa CDR was 0.492 for free-hand systems and 0.500 for fixed-hand systems. There was no significant difference between free-hand and fixed-arm cancer detection rates for both overall PCa (P = .88) and csPCa (P = .90). Subgroup analyses revealed significant PCa CDR and csPCa CDR differences (P < .001) between free-hand and fixed-arm platforms only when 2 cores per lesion were taken, in favor of fixed-arm platforms.

CONCLUSIONS

Fixed-arm platforms performed similarly in cancer detection to free-hand platforms but show a minor benefit on fewer samples. While tracking methodology differences appear subtle, further investigation into the clinical impact of platform-specific features are warranted.

Diagnosis and Pathologic Reporting of Prostate Cancer in the Era of MRI-Targeted Prostate Biopsy

Historically, the detection of prostate cancer relied upon a systematic yet random sampling of the prostate by transrectal ultrasound guided biopsy. This approach was a nontargeted technique that led to the under detection of cancers at biopsy and the upgrading of cancers at radical prostatectomy. Multiparametric MRI-targeted prostate biopsy allows for an image-directed approach to the identification of prostate cancer. MRI-targeted biopsy of the prostate is superior for the detection of clinically significant prostate cancer. As this technique has become more prevalent among urologists, pathologists need to recognize how this development impacts cancer diagnosis and reporting.

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.

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.

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.

Active surveillance inclusion criteria under scrutiny in magnetic resonance imaging-guided prostate biopsy: a multicenter cohort study

BACKGROUND

Although multiparametric magnetic resonance imaging (mpMRI) is recommended for primary risk stratification and follow-up in Active Surveillance (AS), it is not part of common AS inclusion criteria. The objective was to compare AS eligibility by systematic biopsy (SB) and combined MRI-targeted (MRI-TB) and SB within real-world data using current AS guidelines.

METHODS

A retrospective multicenter study was conducted by a German prostate cancer (PCa) working group representing six tertiary referral centers and one outpatient practice. Men with PCa and at least one MRI-visible lesion according to Prostate Imaging Reporting and Data System (PI-RADS) v2 were included. Twenty different AS inclusion criteria of international guidelines were applied to calculate AS eligibility using either a SB or a combined MRI-TB and SB. Reasons for AS exclusion were assessed.

RESULTS

Of 1941 patients with PCa, per guideline, 583-1112 patients with PCa in both MRI-TB and SB were available for analysis. Using SB, a median of 22.1% (range 6.4-72.4%) were eligible for AS. Using the combined approach, a median of 15% (range 1.7-68.3%) were eligible for AS. Addition of MRI-TB led to a 32.1% reduction of suitable patients. Besides Gleason Score upgrading, the maximum number of positive cores were the most frequent exclusion criterion. Variability in MRI and biopsy protocols potentially limit the results.

CONCLUSIONS

Only a moderate number of patients with PCa can be monitored by AS to defer active treatment using current guidelines for inclusion in a real-world setting. By an additional MRI-TB, this number is markedly reduced. These results underline the need for a contemporary adjustment of AS inclusion criteria.

A prospective study on inter-operator variability in semi-robotic software-based MRI/TRUS-fusion targeted prostate biopsies

Purpose

Magnetic resonance imaging (MRI)/ultrasound-fusion prostate biopsy (FB) comprises multiple steps each of which can cause alterations in targeted biopsy (TB) accuracy leading to false-negative results. The aim was to assess the inter-operator variability of software-based fusion TB by targeting the same MRI-lesions by different urologists.

Methods

In this prospective study, 142 patients eligible for analysis underwent software-based FB. TB of all lesions (n = 172) were carried out by two different urologists per patient (n = 31 urologists). We analyzed the number of mismatches [overall prostate cancer (PCa), clinically significant PCa (csPCa) and non-significant PCa (nsPCa)] between both performed TB per patient. In addition we evaluated factors contributing to inter-operator variability by uni- and multivariable analyses.

Results

In 11.6% of all MRI-lesions (10.6% of all patients) there was a mismatch between TB1 and TB2 in terms of overall prostate cancer (PCa detection. Regarding csPCa, patient-based mismatch occurred in 14.8% (n = 21). Overall PCa and csPCa detection rate of TB1 and TB2 did not differ significantly on a per-patient and per-lesion level.

Analyses revealed a smaller lesion size as predictive for mismatches (OR 9.19, 95% CI 2.02–41.83, p < 0.001).

Conclusion

Reproducibility and precision of targeting particularly small lesions is still limited although using software-based FB. Further improvements in image-fusion, segmentation, needle-guidance, and automatization are necessary.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00345-021-03891-3.

Prostate Magnetic Resonance Imaging Analyses, Clinical Parameters, and Preoperative Nomograms in the Prediction of Extraprostatic Extension

Introduction: Proper planning of laparoscopic radical prostatectomy (RP) in patients with prostate cancer (PCa) is crucial to achieving good oncological results with the possibility of preserving potency and continence. Aim: The aim of this study was to identify the radiological and clinical parameters that can predict the risk of extraprostatic extension (EPE) for a specific site of the prostate. Predictive models and multiparametric magnetic resonance imaging (mpMRI) data from patients qualified for RP were compared. Material and methods: The study included 61 patients who underwent laparoscopic RP. mpMRI preceded transrectal systematic and cognitive fusion biopsy. Martini, Memorial Sloan-Kettering Cancer Center (MSKCC), and Partin Tables nomograms were used to assess the risk of EPE. The area under the curve (AUC) was calculated for the models and compared. Univariate and multivariate logistic regression analyses were used to determine the combination of variables that best predicted EPE risk based on final histopathology. Results: The combination of mpMRI indicating or suspecting EPE (odds ratio (OR) = 7.49 (2.31–24.27), p < 0.001) and PSA ≥ 20 ng/mL (OR = 12.06 (1.1–132.15), p = 0.04) best predicted the risk of EPE for a specific side of the prostate. For the prediction of ipsilateral EPE risk, the AUC for Martini’s nomogram vs. mpMRI was 0.73 (p < 0.001) vs. 0.63 (p = 0.005), respectively (p = 0.131). The assessment of a non-specific site of EPE by MSKCC vs. Partin Tables showed AUC values of 0.71 (p = 0.007) vs. 0.63 (p = 0.074), respectively (p = 0.211). Conclusions: The combined use of mpMRI, the results of the systematic and targeted biopsy, and prostate-specific antigen baseline can effectively predict ipsilateral EPE (pT3 stage).

The effect of heated lidocaine gel on pain reduction during transrectal ultrasound-guided prostate biopsy: a randomized-controlled study

PURPOSE

To determine whether intrarectal local anesthesia (IRLA) with heated lidocaine gel provides pain reduction during transrectal ultrasound (TRUS)-guided prostate biopsy.

METHODS

We conducted a randomized-controlled study with 153 participants who underwent TRUS-guided, systematic 12-core prostate biopsy from May 2018 to June 2019. These participants were divided into three test groups. Before prostate biopsy, group A (51 patients) received no local anesthesia, group B (51 patients) received IRLA with 20 mL 2% lidocaine gel stored at room temperature, and group C (51 patients) received IRLA with heated (40 ℃) 20 mL 2% lidocaine gel. Pain was assessed using the 0-10 visual analogue scale (VAS) at three time points: VAS-1: during probe insertion, VAS-2: during biopsy, VAS-3: 30 min after the procedure. Complications during and after the procedure were evaluated.

RESULTS

The mean VAS-2 score was significantly lower in group C compared to groups A and B (A, 4.6; B, 4.2; and C, 3.2; p < 0.05). There was no significant difference among the three groups in mean VAS-1 and VAS-3 scores. No significant difference was detected in incidence of complications between the three groups. No allergic reactions to lidocaine gel were observed.

CONCLUSION

IRLA with heated lidocaine gel provides more effective pain control during TRUS-guided prostate biopsy than does conventional IRLA and no local anesthesia, without an increase of complications.

Is transrectal ultrasound-guided systematic biopsy necessary after PI-RADS 4 is targeted?

Purpose: Target biopsy is usually performed in Prostate Imaging Reporting and Data System (PI-RADS) 4. Still, it is unclear if adding systematic biopsy to target biopsy influences cancer detection. The aim was to assess the role of systematic biopsy for detecting significant cancer after PI-RADS 4 is targeted.Methods: Between March 2014 and November 2018, 182 men with PI-RADS 4 underwent transrectal ultrasound (TRUS)-guided biopsy. Systematic biopsy was added to target biopsy in 128 men (Group I) by May 2018 because PI-RADS 4 was not completely visible on TRUS, while it was done in 54 men (Group II) from June 2018 regardless of lesion visibility. Significant cancer detection rates (CDRs) were compared between the groups regarding target and systematic biopsies. Major complication rate was also compared. Significant cancer was defined as a Gleason score ≥7 tumor. Standard reference was biopsy examination. Fisher’s exact were used for statistical analysis.Results: The significant CDRs were 21.9% (28/128) in the Group I and 38.9% (21/54) in the Group II (P= 0.0273). The significant cancers of Group I and II were missed in two (1.6%) and in one (1.9%) by target biopsy, respectively. Major complication rates of these groups were 0.8% (1/128) and 0% (0/54), respectively (P= 0.999).Conclusion: Systematic biopsy should be added to target biopsy even though PI-RADS 4 is clearly visible on ultrasound. A significant number of significant cancers are detected with systematic biopsy.

Increasing rates of NCCN high and very high-risk prostate cancer versus number of prostate biopsy cores

BACKGROUND

Recently, an increase in the rates of high-risk prostate cancer (PCa) was reported. We tested whether the rates of and low, intermediate, high and very high-risk PCa changed over time. We also tested whether the number of prostate biopsy cores contributed to changes rates over time.

METHODS

Within the Surveillance, Epidemiology and End Results (SEER) database (2010-2015), annual rates of low, intermediate, high-risk according to traditional National Comprehensive Cancer Network (NCCN) and high versus very high-risk PCa according to Johns Hopkins classification were tabulated without and with adjustment for the number of prostate biopsy cores.

RESULTS

In 119,574 eligible prostate cancer patients, the rates of NCCN low, intermediate, and high-risk PCa were, respectively, 29.7%, 47.8%, and 22.5%. Of high-risk patients, 39.6% and 60.4% fulfilled high and very high-risk criteria. Without adjustment for number of prostate biopsy cores, the estimated annual percentage changes (EAPC) for low, intermediate, high and very high-risk were respectively -5.5% (32.4%-24.9%, p < .01), +0.5% (47.6%-48.4%, p = .09), +4.1% (8.2%-9.9%, p < .01), and +8.9% (11.8%-16.9%, p < .01), between 2010 and 2015. After adjustment for number of prostate biopsy cores, differences in rates over time disappeared and ranged from 29.8%-29.7% for low risk, 47.9%-47.9% for intermediate risk, 8.9%-9.0% for high-risk, and 13.6%-13.6% for very high-risk PCa (all p > .05).

CONCLUSIONS

The rates of high and very high-risk PCa are strongly associated with the number of prostate biopsy cores, that in turn may be driven by broader use magnetic resonance imaging (MRI).

Comparative Effectiveness and Tolerability of Transperineal MRI-Targeted Prostate Biopsy under Local versus Sedation

OBJECTIVES

To assess the prostate cancer diagnostic yield, complications, and costs of transperineal prostate biopsies when performed with local anesthesia versus sedation.

METHODS

Data were prospectively collected for men undergoing transperineal MRI-targeted biopsy at the outpatient clinic and tertiary hospital of a single center between October 2017 to February 2020. These data included demographic, procedural, and pathologic variables and complications. Time-driven activity-based costing was performed to compare procedural costs.

RESULTS

126 men were included. Age, BMI and PSA were similar for local (n = 45) vs sedation (n = 81), all P>0.05. Detection of clinically significant prostate cancer (CSPC) on combined systematic and targeted biopsy was similar for local vs sedation (24% vs 36%; P = 0.2). Local had lower detection on targeted biopsies alone (8.9% vs 25%; P = 0.03). However, fewer targeted cores were obtained per region of interest with local vs sedation (median 3 vs 4 cores; P<0.01). For local vs sedation, the complication rate was 2.6% and 6.1% (P = 0.6). The median visual analog pain score for local vs sedation was 3/10 vs 0/10 (P<0.01). The mean procedure time for local vs sedation was 22.5 vs 17.5 minutes (48.3 minutes when including anesthesia time). Time-driven activity-based costs for local vs sedation were $961.64 vs $2208.16 (P<0.01).

CONCLUSION

Transperineal biopsy with local anesthesia is safe with comparable outcomes to sedation. While the number of cores taken differed, there was no statistical difference in the detection of clinically significant cancer.

Number of cores needed to diagnose prostate cancer during MRI targeted biopsy decreases after the learning curve

INTRODUCTION

We hypothesized that the number of cores needed to detect prostate cancer would decrease with increasing MRI-targeted biopsy (TBx) experience.

METHODS

All patients undergoing TBx at our institution from May 2017 to August 2019 were enrolled in a prospectively maintained database. Five biopsy cores were obtained from each lesion ≥3 on PI-RADS v2.0 followed by a systematic 12-core biopsy. To assess learning curve, the study population was divided into quartiles by sequential biopsies. Clinically significant prostate cancer (csPC) was defined as Gleason Grade Group 2 or higher.

RESULTS

377 patients underwent prostate biopsy (533 lesions); 233 lesions (44%) were positive for prostate cancer and 173 lesions (32%) were csPC. There was a significant decline in the number of cores required for diagnosing any cancer (P < 0.001) and csPC (P < 0.05) after the first quartile. There was no difference when stratifying by PI-RADS score or lesion volume. Within the first quartile, limiting the biopsy to 3 cores would miss 16.2% of csPC, decreasing to 6.6% after approximately 100 patients.

CONCLUSION

MRI TBx is associated with a learning curve of approximately 100 cases. Four or 5 cores should be considered during the initial experience, but thereafter, 3 cores per lesion is sufficient to detect csPC.

The 2019 Genitourinary Pathology Society (GUPS) White Paper on Contemporary Grading of Prostate Cancer

CONTEXT.—

Controversies and uncertainty persist in prostate cancer grading.

OBJECTIVE.—

To update grading recommendations.

DATA SOURCES.—

Critical review of the literature along with pathology and clinician surveys.

CONCLUSIONS.—

Percent Gleason pattern 4 (%GP4) is as follows: (1) report %GP4 in needle biopsy with Grade Groups (GrGp) 2 and 3, and in needle biopsy on other parts (jars) of lower grade in cases with at least 1 part showing Gleason score (GS) 4 + 4 = 8; and (2) report %GP4: less than 5% or less than 10% and 10% increments thereafter. Tertiary grade patterns are as follows: (1) replace "tertiary grade pattern" in radical prostatectomy (RP) with "minor tertiary pattern 5 (TP5)," and only use in RP with GrGp 2 or 3 with less than 5% Gleason pattern 5; and (2) minor TP5 is noted along with the GS, with the GrGp based on the GS. Global score and magnetic resonance imaging (MRI)-targeted biopsies are as follows: (1) when multiple undesignated cores are taken from a single MRI-targeted lesion, an overall grade for that lesion is given as if all the involved cores were one long core; and (2) if providing a global score, when different scores are found in the standard and the MRI-targeted biopsy, give a single global score (factoring both the systematic standard and the MRI-targeted positive cores). Grade Groups are as follows: (1) Grade Groups (GrGp) is the terminology adopted by major world organizations; and (2) retain GS 3 + 5 = 8 in GrGp 4. Cribriform carcinoma is as follows: (1) report the presence or absence of cribriform glands in biopsy and RP with Gleason pattern 4 carcinoma. Intraductal carcinoma (IDC-P) is as follows: (1) report IDC-P in biopsy and RP; (2) use criteria based on dense cribriform glands (>50% of the gland is composed of epithelium relative to luminal spaces) and/or solid nests and/or marked pleomorphism/necrosis; (3) it is not necessary to perform basal cell immunostains on biopsy and RP to identify IDC-P if the results would not change the overall (highest) GS/GrGp part per case; (4) do not include IDC-P in determining the final GS/GrGp on biopsy and/or RP; and (5) "atypical intraductal proliferation (AIP)" is preferred for an intraductal proliferation of prostatic secretory cells which shows a greater degree of architectural complexity and/or cytological atypia than typical high-grade prostatic intraepithelial neoplasia, yet falling short of the strict diagnostic threshold for IDC-P. Molecular testing is as follows: (1) Ki67 is not ready for routine clinical use; (2) additional studies of active surveillance cohorts are needed to establish the utility of PTEN in this setting; and (3) dedicated studies of RNA-based assays in active surveillance populations are needed to substantiate the utility of these expensive tests in this setting. Artificial intelligence and novel grading schema are as follows: (1) incorporating reactive stromal grade, percent GP4, minor tertiary GP5, and cribriform/intraductal carcinoma are not ready for adoption in current practice.

Using Prostate Imaging-Reporting and Data System (PI-RADS) Scores to Select an Optimal Prostate Biopsy Method: A Secondary Analysis of the Trio Study

BACKGROUND

While magnetic resonance imaging (MRI)-targeted biopsy (TBx) results in better prostate cancer (PCa) detection relative to systematic biopsy (SBx), the combination of both methods increases clinically significant PCa detection relative to either Bx method alone. However, combined Bx subjects patients to higher number of Bx cores and greater detection of clinically insignificant PCa.

OBJECTIVE

To determine if prebiopsy prostate MRI can identify men who could forgo combined Bx without a substantial risk of missing clinically significant PCa (csPC).

DESIGN, SETTING, AND PARTICIPANTS

Men with MRI-visible prostate lesions underwent combined TBx plus SBx.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The primary outcomes were detection rates for grade group (GG) ≥2 and GG ≥3 PCa by TBx and SBx, stratified by Prostate Imaging-Reporting and Data System (PI-RADS) score.

RESULTS AND LIMITATIONS

Among PI-RADS 5 cases, nearly all csPCs were detected by TBx, as adding SBx resulted in detection of only 2.5% more GG ≥2 cancers. Among PI-RADS 3-4 cases, however, SBx addition resulted in detection of substantially more csPCs than TBx alone (7.5% vs 8%). Conversely, TBx added little to detection of csPC among men with PI-RADS 2 lesions (2%) relative to SBx (7.8%).

CONCLUSIONS

While combined Bx increases the detection of csPC among men with MRI-visible prostate lesions, this benefit was largely restricted to PI-RADS 3-4 lesions. Using a strategy of TBx only for PI-RADS 5 and combined Bx only for PI-RADS 3-4 would avoid excess biopsies for men with PI-RADS 5 lesions while resulting in a low risk of missing csPC (1%).

PATIENT SUMMARY

Our study investigated an optimized strategy to diagnose aggressive prostate cancer in men with an abnormal prostate MRI (magnetic resonance imaging) scan while minimizing the risk of excess biopsies. We used a scoring system for MRI scan images called PI-RADS. The results show that MRI-targeted biopsies alone could be used for men with a PI-RADS score of 5, while men with a PI-RADS score of 3 or 4 would benefit from a combination of MRI-targeted biopsy and systematic biopsy. This trial is registered at ClinicalTrials.gov as NCT00102544.

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

OBJECTIVE

To determine the incremental detection rate of clinically significant prostate cancer (csPCa) provided by sequential cores during in-bore magnetic resonance imaging (MRI)-guided prostate biopsies.

METHODS

Single-center, retrospective interpretation of prospectively acquired data in men without previous diagnosis of csPCa who underwent in-bore MRI-guided prostate biopsy between May 2017 and December 2019. Endpoints included detection of csPCa (grade group [GG] ≥ 2) and rate of GG upgrade provided by additional cores. Descriptive statistics presented as mean and standard deviation for the continuous variables, and frequency and percentage for the categorical variables.

RESULTS

Four hundred and forty-three men with 747 lesions met eligibility criteria. Clinically significant prostate cancer was detected in 43.1% (322/747) of the biopsied lesions and GG 2 PCa or greater was identified by the first core in 78.3% (252/322) of them. On a per-core basis, cores 2, 3, 4, and 5 found new csPCa in 6% (42/744), 4% (26/719), 1% (2/137), and 0% (0/11) of the cases. Core biopsy 2, 3, 4, and 5 resulted in GG upgrade in 12% (91/744), 7% (49/719), 7% (9/137), and 0% (0/11) of the lesions, respectively. Each additional core was associated with a mean increase of 5 minutes in the duration of the biopsy.

CONCLUSIONS

In men undergoing in-bore MRI-guided prostate biopsies, 3 targeted cores per lesion provide an optimal trade-off between detection of clinically significant tumors and biopsy duration.

Techniques and Outcomes of MRI-TRUS Fusion Prostate Biopsy

PURPOSE OF REVIEW

The goal of this study is to review recent findings and evaluate the utility of MRI transrectal ultrasound fusion biopsy (FBx) techniques and discuss future directions.

RECENT FINDINGS

FBx detects significantly higher rates of clinically significant prostate cancer (csPCa) than ultrasound-guided systematic prostate biopsy (SBx), particularly in repeat biopsy settings. FBx has also been shown to detect significantly lower rates of clinically insignificant prostate cancer. In addition, a dedicated prostate MRI can assist in more accurately predicting the Gleason score and provide further information regarding the index cancer location, prostate volume, and clinical stage. The ability to accurately evaluate specific lesions is vital to both focal therapy and active surveillance, for treatment selection, planning, and adequate follow-up. FBx has been demonstrated in multiple high-quality studies to have improved performance in diagnosis of csPCa compared to SBx. The combination of FBx with novel technologies including radiomics, prostate-specific membrane antigen positron emission tomography (PSMA PET), and high-resolution micro-ultrasound may have the potential to further enhance this performance.

Positive Predictive Value of Prostate Imaging Reporting and Data System Version 2 for the Detection of Clinically Significant Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT

The variability of the positive predictive value (PPV) represents a significant factor affecting the diagnostic performance of multiparametric magnetic resonance imaging (mpMRI).

OBJECTIVE

To analyze published studies reporting mpMRI PPV and the reasons behind the variability of clinically significant prostate cancer (csPCa) detection rates on targeted biopsies (TBx) according to Prostate Imaging Reporting and Data System (PI-RADS) version 2 categories.

EVIDENCE ACQUISITION

A search of PubMed, Cochrane library's Central, EMBASE, MEDLINE, and Scopus databases, from January 2015 to June 2020, was conducted. The primary and secondary outcomes were to evaluate the PPV of PI-RADS version 2 in detecting csPCa and any prostate cancer (PCa), respectively. Individual authors' definitions for csPCa and PI-RADS thresholds for positive mpMRI were accepted. Detection rates, used as a surrogate of PPV, were pooled using random-effect models. Preplanned subgroup analyses tested PPV after stratification for PI-RADS scores, previous biopsy status, TBx technique, and number of sampled cores. PPV variation over cancer prevalence was evaluated.

EVIDENCE SYNTHESIS

Fifty-six studies, with a total of 16 537 participants, were included in the quantitative synthesis. The PPV of suspicious mpMRI for csPCa was 40% (95% confidence interval 36-43%), with large heterogeneity between studies (I² 94%, p < 0.01). PPV increased according to PCa prevalence. In subgroup analyses, PPVs for csPCa were 13%, 40%, and 69% for, respectively, PI-RADS 3, 4, and 5 (p < 0.001). TBx missed 6%, 6%, and 5% of csPCa in PI-RADS 3, 4, and 5 lesions, respectively. In biopsy-naïve and prior negative biopsy groups, PPVs for csPCa were 42% and 32%, respectively (p = 0.005). Study design, TBx technique, and number of sampled cores did not affect PPV.

CONCLUSIONS

Our meta-analysis underlines that the PPV of mpMRI is strongly dependent on the disease prevalence, and that the main factors affecting PPV are PI-RADS version 2 scores and prior biopsy status. A substantially low PPV for PI-RADS 3 lesions was reported, while it was still suboptimal in PI-RADS 4 and 5 lesions. Lastly, even if the added value of a systematic biopsy for csPCa is relatively low, this rate can improve patient risk assessment and staging.

PATIENT SUMMARY

Targeted biopsy of Prostate Imaging Reporting and Data System 3 lesions should be considered carefully in light of additional individual risk assessment corroborating the presence of clinically significant prostate cancer. On the contrary, the positive predictive value of highly suspicious lesions is not high enough to omit systematic prostate sampling.

Delivering Clinical impacts of the MRI diagnostic pathway in prostate cancer diagnosis

Pre-biopsy multiparametric MRI is now recommended by multiple guidelines, not only for men with persistent suspicion of prostate cancer after prior negative systematic biopsy, but also at initial screening before the first biopsy. The major benefit of pre-biopsy MRI in the diagnostic work-up is to promote individualized risk-adapted approaches for biopsy-decision management. Multiple MRI-directed diagnostic pathways can be conceived, with each approach having net-benefit trade-offs between benefits and harms, based on improved diagnostic yields of significant cancers and reduced biopsy testing and reduced detection of indolent prostate cancer. In this paper, we illustrate how clinical benefits can be maximized in men with MRI-negative and MRI-positive results, using the PI-RADS Multiparametric MRI and MRI-directed biopsy pathway. From a practice perspective, we emphasize five golden rules: (1) that multiparametric MRI approach including targeted biopsies be reserved for men likely to benefit from early detection and treatment of prostate cancer; (2) that there is a need to carefully assess risk of significant disease using PSA and clinical parameters before and after MRI; (3) do not offer immediate biopsy if the MRI is negative, unless other high-risk factors are present; (4) accept that not all significant cancers are found immediately and have robust 'safety nets' for men with negative MRI scans who avoid immediate biopsy and for positive MRI patients with negative or non-explanatory histology; and (5) use MRI-directed biopsy methods that minimize overdiagnosis and improve risk stratification.

EAU-EANM-ESTRO-ESUR-SIOG Guidelines on Prostate Cancer-2020 Update. Part 1: Screening, Diagnosis, and Local Treatment with Curative Intent

OBJECTIVE

To present a summary of the 2020 version of the European Association of Urology (EAU)-European Association of Nuclear Medicine (EANM)-European Society for Radiotherapy and Oncology (ESTRO)-European Society of Urogenital Radiology (ESUR)-International Society of Geriatric Oncology (SIOG) guidelines on screening, diagnosis, and local treatment of clinically localised prostate cancer (PCa).

EVIDENCE ACQUISITION

The panel performed a literature review of new data, covering the time frame between 2016 and 2020. The guidelines were updated and a strength rating for each recommendation was added based on a systematic review of the evidence.

EVIDENCE SYNTHESIS

A risk-adapted strategy for identifying men who may develop PCa is advised, generally commencing at 50 yr of age and based on individualised life expectancy. Risk-adapted screening should be offered to men at increased risk from the age of 45 yr and to breast cancer susceptibility gene (BRCA) mutation carriers, who have been confirmed to be at risk of early and aggressive disease (mainly BRAC2), from around 40 yr of age. The use of multiparametric magnetic resonance imaging in order to avoid unnecessary biopsies is recommended. When a biopsy is performed, a combination of targeted and systematic biopsies must be offered. There is currently no place for the routine use of tissue-based biomarkers. Whilst prostate-specific membrane antigen positron emission tomography computed tomography is the most sensitive staging procedure, the lack of outcome benefit remains a major limitation. Active surveillance (AS) should always be discussed with low-risk patients, as well as with selected intermediate-risk patients with favourable International Society of Urological Pathology (ISUP) 2 lesions. Local therapies are addressed, as well as the AS journey and the management of persistent prostate-specific antigen after surgery. A strong recommendation to consider moderate hypofractionation in intermediate-risk patients is provided. Patients with cN1 PCa should be offered a local treatment combined with long-term hormonal treatment.

CONCLUSIONS

The evidence in the field of diagnosis, staging, and treatment of localised PCa is evolving rapidly. The 2020 EAU-EANM-ESTRO-ESUR-SIOG guidelines on PCa summarise the most recent findings and advice for their use in clinical practice. These PCa guidelines reflect the multidisciplinary nature of PCa management.

PATIENT SUMMARY

Updated prostate cancer guidelines are presented, addressing screening, diagnosis, and local treatment with curative intent. These guidelines rely on the available scientific evidence, and new insights will need to be considered and included on a regular basis. In some cases, the supporting evidence for new treatment options is not yet strong enough to provide a recommendation, which is why continuous updating is important. Patients must be fully informed of all relevant options and, together with their treating physicians, decide on the most optimal management for them.

Optimizing MRI-targeted prostate biopsy: the diagnostic benefit of additional targeted biopsy cores

INTRODUCTION

The optimal number of biopsy cores to obtain during MRI-targeted prostate biopsy remains ill-defined. This study sought to determine the optimal number of targeted biopsy cores to obtain from a region of interest to maximize detection of clinically significant prostate cancer.

MATERIALS AND METHODS

Consecutive patients undergoing MRI-targeted prostate biopsy at a single institution that newly implemented a targeted biopsy pathway from May 2017 to February 2018 were prospectively enrolled. Five biopsy cores were obtained and individually analyzed from each region rated ≥3 on PI-RADS v2.0 to determine the incremental diagnostic benefit of each additional targeted biopsy core. Variables associated with increasing Grade Group from the first to fifth biopsy core were assessed.

RESULTS

One hundred and four patients (79% for elevated PSA) were enrolled, 82% of which had a prior biopsy. Men with a PI-RADS >3 lesion were more likely to have pathologic upgrading with additional targeted biopsy cores (OR:4.76; 95% CI:2.34-9.70; P < 0.0001), particularly to Grade Group ≥2 (OR:5.16; 95% CI:2.17-12.29; P = 0.0002), compared to men with PI-RADS 3 lesions. Detection of clinically significant cancer increased from 26% to 44% to 52% when comparing the first, third, and fifth biopsy cores amongst men with a PI-RADS >3 lesion and from 1% to 4% to 9% for PI-RADS 3 lesions. Urinary retention was the most common complication, occurring in 6 (5.7%) patients.

CONCLUSION

Clinically significant prostate cancer detection is improved with increased number of MRI-targeted biopsy cores, particularly for urologists early in their learning curve.

When to biopsy Prostate Imaging and Data Reporting System version 2 (PI-RADSv2) assessment category 3 lesions? Use of clinical and imaging variables to predict cancer diagnosis at targeted biopsy

INTRODUCTION

We aimed to determine if clinical and imaging features can stratify men at higher risk for clinically significant (CS, International Society of Urological Pathology [ISUP] grade group ≥2) prostate cancer (PCa) in equivocal Prostate Imaging and Data Reporting System (PI-RADS) category 3 lesions on magnetic resonance imaging (MRI).

METHODS

Approved by the institutional review board, this retrospective study involved 184 men with 198 lesions who underwent 3T-MRI and MRI-directed transrectal ultrasound biopsy for PI-RADS 3 lesions. Men were evaluated including clinical stage, prostate-specific antigen density (PSAD), indication, and MRI lesion size. Diagnoses for all men and by indication (no cancer, any PCa, CSPCa) were compared using multivariate logistic regression, including stage, PSAD, and lesion size.

RESULTS

We found an overall PCa rate of 31.8% (63/198) and 10.1% (20/198) CSPCa (13 grade group 2, five group 3, and two group 4). Higher stage (p=0.001), PSAD (p=0.007), and lesion size (p=0.015) were associated with CSPCa, with no association between CSPCa and age, PSA, or prostate volume (p>0.05). PSAD modestly predicted CSPCa area under the curve (AUC) 0.66 (95% confidence interval [CI] 0.518-0.794) in all men and 0.64 (0.487-0.799) for those on active surveillance (AS). Model combining clinical stage, PSAD, and lesion size improved accuracy for all men and AS (AUC 0.82 [0.736-0.910], p<0.001 and 0.785 [0.666-0.904], p<0.001). In men with prior negative biopsy and persistent suspicion, PSAD (0.90 [0.767-1.000]) was not different from the model (p>0.05), with optimal cutpoint of ≥0.215 ng/mL/cc achieving sensitivity/specificity of 85.7/84.4%.

CONCLUSIONS

PI-RADSv2 category 3 lesions are often not CSPCa. PSAD predicted CSPCa in men with a prior negative biopsy; however, PSAD alone had limited value, and accuracy improved when using a model incorporating PSAD with clinical stage and MRI lesion size.

Real life data of MRI-targeted biopsy - experience from a single nonacademic centre using cognitive fusion and 1.5 tesla scanning

OBJECTIVES

To date, it is unknown whether systematic biopsies can be safely omitted in patients with unsuspicious MRI findings or if systematic biopsies should be required when targeting focal lesions (PI-RADS 3-5).

METHODS

A series of 366 patients (249 without a previous biopsy) were examined in a 1.5 Tesla MRI scanner. All patients were submitted to systematic biopsies (12-14 regions) with additional targeted biopsies (by cognitive fusion) of focal PI-RADS lesions (PI-RADS 3-5).

RESULTS

In our series, patients with PI-RADS 1/2 findings had rates of adenocarcinoma of any grade, >GG1 and GG4/5 of 34%, 14% and 3%, respectively. The use of MRI prior to biopsy in our series increased the detection of clinically significant prostate cancer (CSPCa) in 28% of patients with focal lesions, and focal lesions were present in 293/366 (80%) of all patients. For CSPCa (>GG1), targeted biopsies improved the diagnosis in 28% of patients, while systematic biopsies resulted in an additional 19% of cancer cases in the series.

CONCLUSION

Systematic biopsies should still be considered in patients with PI-RADS 1/2 findings. Our findings also suggest a stronger benefit of the combined strategy of targeted and systematic biopsies than the findings of previous studies concerning the detection of CSPCa in biopsy-naïve patients.

Evolution of Targeted Prostate Biopsy by Adding Micro-Ultrasound to the Magnetic Resonance Imaging Pathway

BACKGROUND

Although multiparametric magnetic resonance imaging (mpMRI) revolutionized the implementation of prostate biopsies, a considerable amount of clinically significant prostate cancer (csPCa) is missed when performing mpMRI-targeted biopsies only. Microultrasound (micro-US) is a new modality that allows real-time targeting of suspicious regions.

OBJECTIVE

To evaluate micro-US of the prostate with real-time targeting of suspicious regions in patients suspected to have prostate cancer (PCa).

DESIGN, SETTING, AND PARTICIPANTS

We examined 159 patients with prior mpMRI and suspicion of PCa with micro-US in the period from February to December 2018. Micro-US lesions were documented according to the prostate risk identification for micro-US (PRI-MUS) protocol, and were blinded to the mpMRI results and targeted independently of the mpMRI lesions.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The main outcomes were cancer detection rate, additional detection of csPCa, and International Society of Urological Pathology (ISUP) grade group upgrading via micro-US.

RESULTS AND LIMITATIONS

PCa was found in 113/159 (71%) men, with 49% (78/159) having clinically significant cancer (csPCa; ISUP ≥ 2). Micro-US-targeted biopsies resulted in a higher ISUP grade group than the nontargeted biopsies in 26% (42/159), compared with both nontargeted and MRI-targeted biopsies in 16% (26/159). In 17% (27/159) of patients, targeted mpMRI-guided biopsy was negative with cancer identified in the micro-US-guided biopsy, of whom 20 had csPCa. The comparison with only MRI-positive patients is the main limitation of this analysis.

CONCLUSIONS

Our data show an added benefit of micro-US in addition to mpMRI-targeted biopsies in a population of men at risk of PCa. A novel biopsy protocol with solely targeted biopsy with micro-US and mpMRI seems possible, replacing conventional ultrasound and omitting standard systematic biopsies.

PATIENT SUMMARY

In this report, we looked at the performance of microultrasound in the setting of diagnosing prostate cancer. We found that microultrasound is a good addition to magnetic resonance imaging (MRI) of the prostate and presents an alternative for men who may not undergo MRI.

MRI-targeted prostate biopsy: key considerations for pathologists

We discuss the role of the pathologist for MRI-targeted prostate biopsy with a focus on specimen processing, reporting of pathological findings and quality assurance in establishing a successful MRI-targeted biopsy programme. The authors discuss the current issues relevant to pathologists regarding MRI-targeted prostate biopsy. In addition, a brief review of the recently published literature was performed using an English literature search on PubMed with a focus on original investigations related to MRI-targeted prostate biopsy. Our search terms included the following: 'prostate cancer', 'pathology', 'histology', 'reporting', 'cores', 'imaging', 'MRI' and 'mpMRI'. Prostate multiparametric magnetic resonance imaging (mp-MRI) and MRI-targeted biopsy has been shown to improve the diagnosis of clinically significant prostatic adenocarcinoma and can affect the management of patients with prostate cancer. The current active surveillance guidelines were based on data from TRUS biopsies and not MRI-targeted biopsies. MRI-targeted biopsy acquires multiple cores of tissue from one or more suspicious lesions found on mp-MRI. The way in which multiple targeted core biopsies obtained from a single image-directed region of interest are analysed and reported can potentially alter the Gleason score and tumour burden as reported on biopsy, which could undoubtedly alter patient management. Pathologists play an important role in the reporting of MRI-targeted prostate biopsies. How we report prostate cancer grade and extent on these biopsies can influence patient management. In addition, the pathologist should be involved in the quality assurance for patients undergoing MRI-targeted prostate biopsy.

Detection of clinically significant prostate cancer in biopsy-naïve men: direct comparison of systematic biopsy, multiparametric MRI- and contrast-ultrasound-dispersion imaging-targeted biopsy

OBJECTIVES

To compare and evaluate a multiparametric magnetic resonance imaging (mpMRI)-targeted biopsy (TBx) strategy, contrast-ultrasound-dispersion imaging (CUDI)-TBx strategy and systematic biopsy (SBx) strategy for the detection of clinically significant prostate cancer (csPCa) in biopsy-naïve men.

PATIENTS AND METHODS

A prospective, single-centre paired diagnostic study included 150 biopsy-naïve men, from November 2015 to November 2018. All men underwent pre-biopsy mpMRI and CUDI followed by a 12-core SBx taken by an operator blinded from the imaging results. Men with suspicious lesions on mpMRI and/or CUDI also underwent MRI-TRUS fusion-TBx and/or cognitive CUDI-TBx after SBx by a second operator. A non-inferiority analysis of the mpMRI- and CUDI-TBx strategies in comparison with SBx for International Society of Urological Pathology Grade Group [GG] ≥2 PCa in any core with a non-inferiority margin of 1 percentage point was performed. Additional analyses for GG ≥2 PCa with cribriform growth pattern and/or intraductal carcinoma (CR/IDC), and GG ≥3 PCa were performed. Differences in detection rates were tested using McNemar's test with adjusted Wald confidence intervals.

RESULTS

After enrolment of 150 men, an interim analysis was performed. Both the mpMRI- and CUDI-TBx strategies were inferior to SBx for GG ≥2 PCa detection and the study was stopped. SBx found significantly more GG ≥2 PCa: 39% (56/142), as compared with 29% (41/142) and 28% (40/142) for mpMRI-TBx and CUDI-TBx, respectively (P < 0.05). SBx found significantly more GG = 1 PCa: 14% (20/142) compared to 1% (two of 142) and 3% (four of 142) with mpMRI-TBx and CUDI-TBx, respectively (P < 0.05). Detection of GG ≥2 PCa with CR/IDC and GG ≥3 PCa did not differ significantly between the strategies. The mpMRI- and CUDI-TBx strategies were comparable in detection but the mpMRI-TBx strategy had less false-positive findings (18% vs 53%).

CONCLUSIONS

In our study in biopsy-naïve men, the mpMRI- and CUDI-TBx strategies had comparable PCa detection rates, but the mpMRI-TBX strategy had the least false-positive findings. Both strategies were inferior to SBx for the detection of GG ≥2 PCa, despite reduced detection of insignificant GG = 1 PCa. Both strategies did not significantly differ from SBx for the detection of GG ≥2 PCa with CR/IDC and GG ≥3 PCa.

The optimal core number and site for MRI-targeted biopsy of prostate? A systematic review and pooled analysis

INTRODUCTION

Prebiopsy multiparametric magnetic resonance imaging (mpMRI) has been increasingly utilized for patients of suspicious prostate cancer (PCa). However, the optimal core number and site for MRI-targeted biopsy have not been clearly elucidated.

EVIDENCE ACQUISITION

A systematic search in Pubmed, Embase and Ovid up to June 2019 was conducted and we identified studies reporting detection details of every MRI-targeted core. The incremental diagnostic value of performing additional cores was pooled on per-lesion analysis. Our secondary outcome concentrated on detection accuracy for cores of different site within one lesion.

EVIDENCE SYNTHESIS

Five studies comprising 2291 patients were identified to elucidate the association between targeted core number and cancer detection rates. Adding the second core to the first one resulted in 19.8% (range: 13.6-26.7%) increase in the detection rate of clinically significant lesions, and adding the third one to the first two resulted in 11.5% (range: 7.8-14.3%) increase. The incremental value of adding the fourth or the fifth core was 6.0% (4.7%, 6.9%) and 4.1% respectively. Four studies arranging MRI-targeted biopsy of more than two cores in well-determined sequences indicated more positive cores with higher cancer grade through center of the lesions.

CONCLUSIONS

Increasing the number of samples per target from one to two, or two to three resulted in a nonnegligible incremental detection rate of clinically significant lesions, while obtaining more than 3 cores per target provided a diminished incremental value. And performing targeted cores accurately through center of the lesions may help improve diagnostic accuracy.

Optimizing prostate biopsy techniques

PURPOSE OF REVIEW

Prostate cancer (PCa) diagnostics have undergone a number of changes as a result of efforts to reduce the detection rate of indolent prostate cancer and to increase the hit rate for clinically significant prostate cancer (csPCa). Here, we look at those studies that have shifted our knowledge and the impact these have had on clinical practice.

RECENT FINDINGS

The introduction of multiparametric MRI (mpMRI) and approaches to active surveillance have changed the landscape in prostate cancer diagnostics, reducing the number of men that need biopsy, but increasing the need for accuracy in mapping the extent of prostate cancer. As mpMRI reporting has become more accurate at predicting PCa, biopsy techniques have also evolved towards lesion (PI-RADS score 3-5) targeted biopsies. Uncertainty remains regarding the preferred approach to targeted biopsy, the need for systematic biopsies, and the place of software ultrasound/MRI fusion or in-bore MRI biopsy techniques versus 'cognitive' fusion techniques.

SUMMARY

Prostate biopsies remain essential for the diagnosis of PCa. But how best to do this? Latest guidelines advocate performing both targeted and systematic biopsies. Traditionally, prostate biopsies have been performed transrectally (TRUS) with hospital readmission rates of around 3% mainly because of infection. Additionally, TRUS prostate biopsies can miss anterior prostatic lesions. The transperineal approach addresses both these issues, but has historically required general anaesthetic such that adoption for front-line diagnostics is very difficult. Recent techniques to undertake transperineal biopsy under local anaesthetic have fundamentally changed this paradigm offering the genuine possibility that in 5 years' time, all front-line diagnostic biopsies will be performed as LATP.

Incorporating mpMRI biopsy data into established pre-RP nomograms: potential impact of an increasingly common clinical scenario

Background:

We examine the practical application of multiparametric MRI (mpMRI) prostate biopsy data using established pre-RP nomograms and its potential implications on RP intraoperative decision-making. We hypothesize that current nomograms are suboptimal in predicting outcomes with mpMRI targeted biopsy (TBx) data.

Materials and methods:

Patients who underwent mpMRI-based TBx prior to RP were assessed using the MSKCC and Briganti nomograms with the following iterations: (1) Targeted (T) (targeted only), (2) Targeted and Systematic (TS) and (3) Targeted Augmented (TA) (targeted core data; assumed negative systematic cores for 12 total cores). Nomogram outcomes, lymph node involvement (LNI), extracapsular extension (ECE), organ-confined disease (OCD), seminal vesicle invasion (SVI), were compared across iterations. Clinically significant impact on management was defined as a change in LNI risk above or below 2% (Δ2) or 5% (Δ5).

Results:

A total of 217 men met inclusion criteria. Overall, the TA iteration had more conservative nomogram outcomes than the T. Moreover, TA better predicted RP pathology for all four outcomes when compared with the T. In the entire cohort, Δ2 and Δ5 were 16.6–25.8% and 20.3–39.2%, respectively. In the subset of 190 patients with targeted and systematic cores, TA was a better approximation of TS outcomes than T in 71% (MSKCC) and 82% (Briganti) of patients.

Conclusion:

In established pre-RP nomograms, mpMRI-based TBx often yield variable and discordant results when compared with systematic biopsies. Future nomograms must better incorporate mpMRI TBx core data. In the interim, augmenting TBx data may serve to bridge the gap.

The Key Combined Value of Multiparametric Magnetic Resonance Imaging, and Magnetic Resonance Imaging-targeted and Concomitant Systematic Biopsies for the Prediction of Adverse Pathological Features in Prostate Cancer Patients Undergoing Radical Prostatectomy

BACKGROUND

The combined role of multiparametric magnetic resonance imaging (mp-MRI), and magnetic resonance imaging (MRI)-targeted and concomitant systematic biopsies in the identification of prostate cancer (PCa) patients at a higher risk of adverse pathology at radical prostatectomy (RP) is still unclear.

OBJECTIVE

To develop novel models to predict extracapsular extension (ECE), seminal vesicle invasion (SVI), or upgrading in patients diagnosed with MRI-targeted and concomitant systematic biopsies.

DESIGN, SETTING, AND PARTICIPANTS

We included 614 men with clinical stage≤T2 at digital rectal examination who underwent MRI-targeted biopsy with concomitant systematic biopsy.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSES

Logistic regression analyses predicting ECE, SVI, and upgrading (ie, a shift from biopsy International Society of Urological Pathology grade group to any higher grade at RP) based on clinical variables with or without mp-MRI features and systematic biopsy information (the percentage of cores with grade group ≥2 PCa) were developed and internally validated. The area under the curve (AUC) was used to identify the models with the highest discrimination. Decision-curve analyses (DCAs) determined the net benefit associated with their use.

RESULTS AND LIMITATIONS

Overall, 333 (54%), 88 (14%), and 169 (27%) patients had ECE, SVI, and upgrading at RP, respectively. The inclusion of mp-MRI data improved the discrimination of clinical models for ECE (67% vs 70%) and SVI (74% vs 76%). Models including mp-MRI, and MRI-targeted and concomitant systematic biopsy information achieved the highest AUC at internal validation for ECE (73%), SVI (81%), and upgrading (73%) and represented the basis for three risk calculators that yield the highest net benefit at DCA.

CONCLUSIONS

Not only mp-MRI and MRI-targeted sampling, but also concomitant systematic biopsies provide significant information to identify patients at a higher risk of adverse pathology. Although omitting systematic prostate sampling at the time of MRI-targeted biopsy might be associated with a reduced risk of detecting insignificant PCa and lower patient discomfort, it reduces the ability to accurately predict pathological features.

PATIENT SUMMARY

The combination of multiparametric magnetic resonance imaging (mp-MRI) with accurate biopsy information on MRI-targeted and systematic biopsies improves the accuracy of multivariable models based on clinical and mp-MRI data alone. Correct mp-MRI interpretation and proper extensive prostate sampling are both needed to predict adverse pathology accurately at radical prostatectomy.

Prostate biopsy: when and how to perform

Prostate cancer, unlike other cancers, has been sampled in a non-targeted, systematic manner in the past three decades. On account of the low volume of prostate sampled despite the multiple cores acquired, systematic transrectal (TRUS) biopsy suffered from low sensitivity in picking up clinically significant prostate cancer. In addition, a significant number of cancers of the anterior, lateral peripheral zone, and the apex were missed as these areas were undersampled or missed during this biopsy protocol. Subsequently, the number of cores acquired was increased with special focus given to targeting the previously undersampled areas. These procedures led to an increase in the complication rates as well as detection of more clinically insignificant cancers. The advent of multiparametric magnetic resonance imaging (MRI) and its high intrinsic tissue contrast enabled better detection of prostate cancer. This led to the introduction of MRI-targeted biopsies with either MRI-TRUS fusion or under direct (in-gantry) guidance. MRI-targeted biopsies increased the percentage of positive cores and detection of clinically significant prostate cancers; however, these are expensive, time-intensive, require significant capital investment and operator expertise. This article describes the indications, workflow, complications, advantages, and disadvantages of TRUS-guided biopsy followed by MRI-guided biopsies.