Manually controlled targeted prostate biopsy with real-time fusion imaging of multiparametric magnetic resonance imaging and transrectal ultrasound: An early experience

Superior detection of significant prostate cancer by transperineal prostate biopsy using MRI-transrectal ultrasound fusion image guidance over cognitive registration

BACKGROUND

The BioJet system allows the fusion of magnetic resonance imaging (MRI) images with real-time transrectal ultrasonography to accurately direct biopsy needles to the target lesions. To date, the superiority of targeted biopsy using the BioJet system over cognitive registration remains unknown.

METHODS

This retrospective study included 171 biopsy-naïve men with elevated prostate-specific antigen (2.5-20 ng/mL) and MRI-positive lesions; 74 and 97 men underwent a four-core targeted biopsy per MRI-positive target lesion and a 14-core systematic biopsy transperineally using the BioJet system and cognitive registration, respectively. Detection rates of significant cancer, defined as grade group ≥ 2 or maximum cancer length ≥ 5 mm, were compared between the BioJet system and cognitive registration using propensity score matching and a multivariate logistic regression model.

RESULTS

After propensity score matching (67 men for each group), the detection rates of significant cancer were significantly higher in the BioJet group than in the cognitive group for both targeted (76% vs. 46%, P = 0.002) and systematic (70% vs. 46%, P = 0.018) biopsy. Multivariate analysis of the entire cohort also showed that the BioJet system was independently associated with significant cancer detection by targeted and systematic biopsy (P < 0.01), along with a higher prostate-specific antigen density and a higher prostate imaging reporting and data system score.

CONCLUSIONS

Transperineal prostate biopsy using the BioJet system is superior to cognitive registration in detecting significant cancer for targeted and systematic biopsies.

Assessing the need for systematic biopsies in addition to targeted biopsies according to the characteristics of the index lesion at mpMRI. Results from a large, multi-institutional database

PURPOSE

We hypothesized that systematic biopsies (SBx) value for clinically significant PCa (csPCa) detection, in addition to mpMRI targeted biopsies (TBx), may vary significantly according to mpMRI index lesion (IL) characteristics.

METHODS

We identified 1350 men with an mpMRI suspicious lesion (PI-RADS ≥ 3), defined as IL, who underwent TBx and SBx at three referral centres. The outcome was SBx added value in csPCa (grade group ≥ 2 PCa detected at SBx and missed by TBx) detection. To this aim, we performed multivariable logistic regression analyses (MVA). Furthermore, we explored the interaction between IL volume and SBx csPCa added value, across different PI-RADS categories, using lowess function.

RESULTS

Overall, 569 (42%) men had csPCa at TBx and 78 (6%) csPCa were identified at SBx only. At MVA PSA (OR 0.90; p < 0.05) and IL volume (OR 0.58; p < 0.05) were associated with SBx csPCa added value. At interaction analyses, a nonlinear correlation between PI-RADS and SBx csPCa added value was identified with a decrease from roughly 10 to 4% followed by a substantial plateau at 1.2 ml and 0.6 ml for PI-RADS 3 and 4, respectively. For PI-RADS 5 lesions SBx csPCa added was constantly lower than 4%.

CONCLUSIONS

Increasing IL volume in PI-RADS 3 and 4 lesions is associated with reduction in SBx csPCa added value. For diagnostic purposes, SBx could be omitted in men with IL larger than 1.2 ml and 0.6 ml for PI-RADS 3 and 4, respectively. Conversely, for PI-RADS 5, SBx csPCa added value was minimal regardless of IL volume.

First experiences and results after cryoablation of prostate cancer with histopathological evaluation and imaging-based follow-up

Aim: To share our experience after 28 cryoablation treatments for prostate cancer (PCa) with histopathology, clinical data and MRI as the follow-up methods. Methods: Clinical follow-up comprised prostate specific antigen (PSA)-measurements, PSA-density and quality-of-life-parameters. multi-parametric (mp)MRI pre- and post-cryoablation were retrospectively re-analyzed in 23 cases using Likert scores. Follow-up-histopathology was performed via MRI/ultrasound fusion-guided and/or systematic biopsy. Receiver operating characteristic curve analysis was performed. Results: 17 PCa (61%) were diagnosed within 12-month post-cryotherapy (infield and out-of-field disease). PSA levels and PSA density were not significantly different between patients with or without PCa recurrence. mpMRI can characterize the decrease in prostate volume and necrosis. Area under the curve for the detection of PCa was 81% (global Likert scores), 74-87% (T2), 78% (diffusion weighted imaging) and 57-78% (dynamic contrast enhanced imaging; Youden-selected cutoff ≥3). Conclusion: Besides histopathological evaluation and control biopsy, MRI might have the potential to accurately detect PCa after cryotherapy. Clinical data and interdisciplinary communication are required for efficient monitoring after cryoablation treatments for PCa.

Development and future prospective of treatment for localized prostate cancer with high-intensity focused ultrasound

High-intensity focused ultrasound (HIFU) was experimentally used for focal therapy for anti-cancer effects in prostate cancer (PC). Focal therapy is a diagnosis-based investigational treatment option for localized PC that cures clinically significant PC (csPC) while preserving the anatomical structures related to urinary and sexual function based on its spread observed using multi-parametric magnetic resonance imaging (mpMRI). The European Association of Urology indicated that the current status of focal therapy for localized PC was an investigational modality and encouraged prospective recording of outcomes and recruitment of suitable patients in 2018. During the last few years, large-population multi- and single-center prospective studies have investigated focal therapy as a treatment strategy for localized PC. In a multicenter prospective study with 5-year follow-up, failure-free survival, which was defined as avoidance of local salvage therapy (surgery or radiotherapy), systemic therapy, metastases, and prostate cancer-specific death, was 88%. In the previous studies, there was no significant influence on urinary function before and at 3 months after the treatment, although transient impairment was reported 1 month after the treatment. Pad- and leak-free continence was preserved in 80-100% of the patients after treatment. Erectile function was significantly impaired in the initial 3 months after treatment compared to the pretreatment values, but it improved 6 months after the focal therapy in the previous reports. Paired comparison studies and cohort studies with long-term follow-up will contribute to verifying this treatment's clinical outcomes for patients with localized PC.

Optimizing prostate-targeted biopsy schemes in men with multiple mpMRI visible lesions: should we target all suspicious areas? Results of a two institution series

BACKGROUND

To assess the diagnostic added value of sampling secondary lesions at prostate mpMRI (SL) in addition to index lesion (IL) in detecting significant prostate cancer (csPCa) when also systematic biopsy (SBx) is performed.

METHODS

We relied on a cohort of 312 men with two suspicious lesions at prostate mpMRI who underwent subsequent targeted biopsy of each lesion (TBx) and concomitant SBx at two tertiary-referral centers between 2013 and 2019. The study outcome was the added value of targeting SL (i.e., the one with a lower PI-RADS score and/or the smaller size compared to IL) in the detection of csPCa. To this aim, we compared different biopsy strategies (SBx + overall TBx vs SBx + IL-targeted biopsy vs SBx + SL-targeted biopsy) and assessed whether SL features could be correlated with detection of csPCa at overall TBx in a multivariable logistic regression model (MVA).

RESULTS

Overall, 44% of men had csPCa at TBx of all lesions while 39% and 23% of men had csPCa found in IL and SL, respectively. The rate of csPCa found at SBx, IL-TBx, and SL-TBx only was 5%, 6%, and 2%, respectively. The detection rate of csPCa for SBx + IL-TBx was 47%. The addition of SL-TBx increased csPCa detection by only 2% (p = 0.12). At MVA, neither PI-RADS of SL nor the number of cores targeting SL was associated with an increased detection of csPCa (all p > 0.3). Conversely, age (OR: 1.07), PSA (OR: 1.07), prostate volume (OR: 0.98), and PI-RADS of the IL (OR: 2.36) were independently associated with csPCa detection at TBx (all p < 0.01).

CONCLUSIONS

There is no significant benefit in terms of csPCa detection when an adequate SBx is performed in combination with IL-TBx in patients with multiple mpMRI lesions. In these men target biopsy of secondary lesions can be safely omitted.

A Prospective Study and Single-Center Experience: Effectivity of Fusion Prostate Biopsy in Biopsy-Naïve Patients

Objective

Fusion prostate biopsy (FPB) has become a popular technique in biopsy-naïve patients, though not accepted as a standard approach (yet). In this study, we aimed to present the clinical outcomes of biopsy-naïve patients who underwent FPB.

Material and methods

The study included 400 biopsy-naïve patients aged 45-75 years who had a prostate-specific antigen (PSA) level of 2-10 ng/ml and were detected with a Prostate Imaging-Reporting and Data System (PIRADS) ≥3 lesion on multiparametric prostate magnetic resonance imaging (mpMRI)-guided FPB. A combined biopsy (CB) was performed in each patient, in which 2-4 cores were obtained for suspicious lesions by targeted biopsy (TB) and then 12-core standard prostate biopsy (SPB) was conducted in the same session. Cancer detection rates, clinically significant prostate cancer (csPCa) detection rates, histological upgrading rates, and false negative rates were determined.

Results

The 400 patients had a mean age of 62.01±7.00 years and a mean PSA value of 6.84±1.87 ng/ml. Overall PCa detection rate was 50% (200/400). The csPCa detection rates for TB, SPB, and CB were 25.0%, 31.8%, and 44.0%, respectively (p<0.001). In PIRADS 3, 4, and 5 lesions, CB had a csPCa detection rate of 29.2%, 54%, and 64.8%, respectively (p<0.001). The ratio of false negativity was significantly higher for TB compared to SPB (43.2% vs. 27.8%, p=0.003), whereas no significant difference was found between these two techniques with regard to upgrading rates although TB had a higher rate (19.6% vs. 13.7%, p=0.144).

Conclusion

FPB, a combined approach involving TB and SPB, was revealed as the most successful technique in biopsy-naïve patients with PSA<10 ng/ml due to its high cancer detection rates and low false negative rates.

How to optimize follow-up in patients with a suspicious multiparametric MRI and a subsequent negative targeted prostate biopsy. Results from a large, single-institution series

OBJECTIVE

We aimed at optimizing the follow-up for patients with a positive multiparametric magnetic resonance of the prostate (mpMRI) and a subsequent negative targeted biopsy (TBx) plus systematic biopsy (SBx).

MATERIALS AND METHODS

A total of 308 men with a clinical suspicion of PCa and a positive mpMRI (PI-RADS ≥ 3) with concomitant negative systematic and targeted Bx performed at a single tertiary referral center. All patients were then followed with serial PSA measurements, digital rectal examination and eventual follow-up mpMRI and/or repeat Bx. The primary outcome was to evaluate the overall clinically significant PCa (csPCa)-free survival. The secondary outcome was to assess the role of a repeat mpMRI (Fu-mpMRI) and PSA density as predictors of csPCa diagnosis (defined as Gleason score ≥ 3 + 4) during follow-up. Kaplan Meier analysis and univariable Cox regression were used for survival and predictive analyses.

RESULTS

Median follow-up was 31 months (IQR: 23-43). During the study period 116 (37.7%) and 68 (22.1%) of men received a Fu-mpMRI and a Fu-Bx, respectively. Overall, 51 (16.6%) and 15 (4.9%) patients had a positive mpMRI and clinically significant (csPCa) diagnosis during follow-up, respectively. Among 68 men who received a Fu-Bx, the 2- and 3-years csPCa diagnosis-free survival in men with negative vs. positive Fu-mpMRI was 97% vs. 65% and 92% vs. 65%, respectively. At univariate Cox-regression analysis the presence of a positive Fu-mpMRI resulted to be significantly associated with the presence of csPCa at Fu-Bx (HR: 5.8, 95% CI: 1.3-26.6, P = 0.008). The 2- and 3-years csPCa diagnosis-free survival in men with PSAd <0.15 vs. ≥0.15 was 89% vs. 77%, and 86% vs. 66%, respectively (HR: 2.6, 95% CI: 0.75-8.87, P = 0.13). The combination of negative Fu-mpMRI and PSAd<0.15 furtherly reduced the probability of csPCa diagnosis at Fu-Bx at only 6% at 3years (HR: 9.9, 95% CI: 1.9-38.6, P < 0.001) in this subgroup of patients.

CONCLUSIONS

After a negative TBx for a positive mpMRI, more than half of Fu-mpMRI were negative. A persistent positive mpMRI was associated with a significant risk of csPCa. The risk of csPCa diagnosis in men with negative mpMRI performed after negative TBx and low PSAd was negligible.

Diagnostic accuracy of magnetic resonance imaging targeted biopsy techniques compared to transrectal ultrasound guided biopsy of the prostate: a systematic review and meta-analysis

Background

Multiparametric MRI localizes cancer in the prostate, allowing for MRI guided biopsy (MRI-GB) 43 alongside transrectal ultrasound-guided systematic biopsy (TRUS-GB). Three MRI-GB approaches exist; visual estimation (COG-TB); fusion software-assisted (FUS-TB) and MRI ‘in-bore’ biopsy (IB-TB). It is unknown whether any of these are superior.

We conducted a systematic review and meta-analysis to address three questions. First, whether MRI-GB is superior to TRUS-GB at detecting clinically significant PCa (csPCa). Second, whether MRI-GB is superior to TRUS-GB at avoiding detection of insignificant PCa. Third, whether any MRI-GB strategy is superior at detecting csPCa.

Methods

A systematic literature review from 2015 to 2019 was performed in accordance with the START recommendations. Studies reporting PCa detection rates, employing MRI-GB and TRUS-GB were included and evaluated using the QUADAS-2 checklist. 1553 studies were found, of which 43 were included in the meta-analysis.

Results

For csPCa, MRI-GB was superior in detection to TRUS-GB (0.83 vs. 0.63 [p = 0.02]). MRI-GB was superior in detection to TRUS-GB at avoiding detection of insignificant PCa. No MRI-GB technique was superior at detecting csPCa (IB-TB 0.87; COG TB 0.81; FUS-TB 0.81, [p = 0.55]). There was significant heterogeneity observed between the included studies.

Conclusions

In patients with suspected PCa on MRI, MRI-GB offers superior rates of csPCa detection and reduces detection of insignificant PCa compared to TRUS-GB. No individual MRI-GB technique was found to be better in csPCa detection. Prospective adequately powered randomized controlled trials are required.

Multiparametric magnetic resonance imaging of the prostate underestimates tumour volume of small visible lesions

OBJECTIVE

To assess the relationship between the volume of the index lesion (IL) measured at multiparametric magnetic resonance imaging (mpMRI; MRIvol) and at radical prostatectomy (RPvol), stratifying it according to Prostate Imaging-Reporting and Data System (PI-RADS) score.

PATIENTS AND METHODS

We identified 332 men with a positive mpMRI (single lesion with PI-RADS ≥3) who underwent systematic plus targeted biopsy and subsequent RP at two tertiary referral centres between 2013 and 2018. All mpMRIs were reviewed by experienced radiologists using PI-RADS scores. The study outcome was to assess the relationship between MRIvol (based on planimetry from MRI sequence best showing tumour) and RPvol (based on tumour involved area of each RP pathology slice). To achieve this endpoint, we performed a multivariable linear regression analysis (LRA) to predict RPvol using PI-RADS, prostate-specific antigen level, prostate volume, age, digital rectal examination, Gleason score at MRI-targeted biopsy, biopsy history and time from mpMRI to RP as covariates. Non-parametric locally estimated scatterplot smoothing (LOESS) function was used to graphically explore the relationship between MRIvol and RPvol, stratifying for PI-RADS score.

RESULTS

Overall, 24%, 49% and 27% of men had visible PI-RADS 3, 4 and 5 lesions at mpMRI. The median (interquartile range [IQR]) MRIvol and RPvol were 0.67 (0.29-1.76) mL and 1.39 (0.58-4.23) mL. At LRA, MRIvol was significantly correlated with a RPvol underestimation (slope: 2.4, 95% confidence interval [CI] 0.1-46.3). The non-parametric LOESS analysis showed a non-linear relationship between MRIvol and RPvol. Significant underestimation was reported across all volumes with the highest differences between MRIvol and RPvol in the low volume range (<2 mL), where RPvol almost doubled MRIvol. A similar effect was observed across all PI-RADS scores subgroups.

CONCLUSIONS

In the present study, mpMRI significantly underestimated the exact volume of the IL, especially for small visible lesions, regardless of PI-RADS score. This should be considered when planning tailored focal therapy approaches often delivered to men with smaller prostatic lesions.

Fourteen-Core Systematic Biopsy That Includes Two Anterior Cores in Men With PI-RADS Lesion ≥ 3 is Comparable With Magnetic Resonance Imaging-ultrasound Fusion Biopsy in Detecting Clinically Significant Prostate Cancer: A Single-institution Experience

INTRODUCTION

Magnetic resonance imaging (MRI)-ultrasound fusion targeted prostate biopsy (FB) has been advocated by many experts as a replacement for the standard template biopsy. Herein, we compared pathology results and cancer detection rates of FB with our standard 14-core systematic prostate biopsy (SB) that includes 2 anterior cores.

MATERIALS AND METHODS

One hundred two men with elevated prostate-specific antigen and suspicious lesions on multiparametric MRI, Prostate Imaging Reporting And Data System (PI-RADS) v2 score ≥ 3, underwent FB. Each target lesion was biopsied 3 times; our SB was performed concurrently. Biopsy results were compared for overall and clinically significant (cs), defined as Gleason score ≥ 7, cancer detection.

RESULTS

Fifty-two percent of patients had positive biopsy results, and of those, 44 had cs prostate cancer (PCa). The overall detection rates for FB and SB were 39% and 50%, respectively, and there was no statistical difference in the detection rate of csPCa detection rate (P = .42). Of 17 patients diagnosed with a high-risk PCa, defined as Gleason score ≥ 8, SB identified 15, whereas FB identified 10. Within the SB group, 21 had positive anterior core biopsies, of which 11 were cs.

CONCLUSION

Expanding the standard template prostate biopsies to include 2 anterior horn sampling may be just as effective as FB in men with PI-RADS lesion ≥ 3, thereby mitigating the increased cost associated with FB.

Comparison of Real-Time Virtual Sonography Navigation Versus BioJet Navigation on Magnetic Resonance Imaging-Guided Prostate Needle Biopsy: A Single Institutional Analysis

Objective: To analyze the effectiveness and complication rate of MRI-guided prostate needle biopsies by using real-time virtual sonography (RVS) vs BioJet navigation. Methods: We retrospectively reviewed 171 patients who underwent an MRI-guided prostate needle biopsy at our institution. Patients whose prostate-specific antigen level was >4.0 ng/mL and who had suspicious prostate cancer (PCa) lesions by multiparametric MRI (mpMRI) underwent 2-core MRI-guided targeted biopsy (TB) and for MRI-guided TB: RVS and BioJet. RVS navigation synchronized mpMRI images with transrectal ultrasound (TRUS) images. BioJet navigation used a software program that merged images from mpMRI and TRUS to produce a composite image. We retrospectively compared the detection rate of PCa and the frequency of severe adverse events (AEs) between these two navigation systems, focusing on patients. In addition, we compared the detection rate of MRI-guided TB cores of two navigation systems regarding anatomical position (transitional zone [TZ] or peripheral zone [PZ]). Results: Data from RVS and BioJet biopsy groups were from 65 and 106 patients, respectively. Of these, RVS-TB included 141 cores (PZ: 49 cores, TZ: 92 cores), and BioJet-TB included 276 cores (PZ: 73 cores, TZ: 203 cores). In detecting PCa, by conducting both systematic biopsy and TB, and AEs in patients, a significant difference was not noted between RVS and BioJet navigation systems. In addition, there was no significant difference in the total detection rate for PCa in TB cores between the two methods. However, in the TZ, BioJet navigation showed a significantly higher detection rate of PCa than RVS navigation (35.0% vs 17.4%, p = 0.0023) by analyzing the cores of MRI-guided TB. Conclusion: When targeting TZ lesions, BioJet navigation had a greater detection rate for PCa compared with that of RVS navigation.

The role of MRI/TRUS fusion biopsy in the diagnosis of clinically significant prostate cancer

Background

The aim of this work is to evaluate the detection rate of magnetic resonance imaging/transrectal ultrasound (MRI/TRUS) fusion-guided biopsy for clinically significant prostate cancers (Cs PCas), with particular interest in biopsy-naive patients and patients in active surveillance. MRI-targeted biopsy improves cancer detection rate (DR) in patients with prior negative biopsies; the current literature focuses on biopsy naive patients. We also evaluated the pathologic concordance between biopsies and surgical specimens.

Methods

MRI/TRUS fusion-guided biopsies were performed between February 2016 and February 2019. Patients with previous negative biopsies, biopsy-naive or in active surveillance (AS) were included. Cs PCas were defined through Epstein's criteria.

Results

A total of 416 men were enrolled. The overall DRs and Cs PCa DRs were 49% and 34.3%, respectively. Cs PCas were 17.2%, 44.9% and 73.4%, respectively for PI-RADS 3, 4 or 5. Among biopsy-naive patients, 34.8% were found to have a Cs PCa, while a 43.6% tumour upgrading was achieved in men with a low risk of PCa. In patients who underwent radical prostatectomy (RP), the concordance between biopsy Gleason score (GS) (bGS) and pathological GS (pGS) was 90.8%.

Conclusion

Our study highlights the role of MRI/TRUS fusion prostate biopsy in the detection of PCa in patients with previous negative biopsies focusing on Cs PCa diagnosis. The MRI/TRUS fusion biopsy is also emerging as a diagnostic tool in biopsy-naïve patients and deserves a fundamental role in AS protocols. A greater concordance between bGS and pGS can be achieved with targeted biopsies.

Magnetic Resonance Imaging-targeted Biopsy Versus Systematic Biopsy in the Detection of Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT

Magnetic resonance imaging (MRI)-targeted prostate biopsy (MRI-TB) may be an alternative to systematic biopsy for diagnosing prostate cancer.

OBJECTIVE

The primary aims of this systematic review and meta-analysis were to compare the detection rates of clinically significant and clinically insignificant cancer by MRI-TB with those by systematic biopsy in men undergoing prostate biopsy to identify prostate cancer.

EVIDENCE ACQUISITION

A literature search was conducted using the PubMed, Embase, Web of Science, Cochrane library, and Clinicaltrials.gov databases. We included prospective and retrospective paired studies where the index test was MRI-TB and the comparator test was systematic biopsy. We also included randomised controlled trials (RCTs) if one arm included MRI-TB and another arm included systematic biopsy. The risk of bias was assessed using a modified Quality Assessment of Diagnostic Accuracy Studies-2 checklist. In addition, the Cochrane risk of bias 2.0 tool was used for RCTs.

EVIDENCE SYNTHESIS

We included 68 studies with a paired design and eight RCTs, comprising a total of 14709 men who either received both MRI-TB and systematic biopsy, or were randomised to receive one of the tests. MRI-TB detected more men with clinically significant cancer than systematic biopsy (detection ratio [DR] 1.16 [95% confidence interval {CI} 1.09-1.24], p<0.0001) and fewer men with clinically insignificant cancer than systematic biopsy (DR 0.66 [95% CI 0.57-0.76], p<0.0001). The proportion of cores positive for cancer was greater for MRI-TB than for systematic biopsy (relative risk 3.17 [95% CI 2.82-3.56], p<0.0001).

CONCLUSIONS

MRI-TB is an attractive alternative diagnostic strategy to systematic biopsy.

PATIENT SUMMARY

We evaluated the published literature, comparing two methods of diagnosing prostate cancer. We found that biopsies targeted to suspicious areas on magnetic resonance imaging were better at detecting prostate cancer that needs to be treated and avoiding the diagnosis of disease that does not need treatment than the traditional systematic biopsy.

Applicability of readout-segmented echoplanar diffusion weighted imaging for prostate MRI

To evaluate readout-segmented echoplanar (rsEPI) diffusion weighted imaging (DWI) for multiparametric (mp) magnetic resonance imaging (MRI) of the prostate compared to the established single-shot echoplanar imaging (ssEPI) sequence.One hundred ten consecutive patients with clinical suspicion of prostate cancer underwent mp prostate MRI using both, the ssEPI and the rsEPI DWI sequence. For an objective assessment, delineation of the prostate shape on both DWI sequences was compared to T2-weighted images by measuring organ diameters. Apparent diffusion coefficient (ADC) values, image contrast and contrast-to-noise ratio (CNR) were compared between the 2 sequences on a region-of-interest-based analysis. Diagnostic accuracy for quantitative ADC-values was calculated. Histopathology from MRI/ultrasound fusion-guided biopsy was used as reference standard. For a subjective assessment, 2 independent readers visually assessed image quality of both sequences using Likert-scales.Delineation of the prostate shape was more accurate with rsEPI compared to ssEPI. ADC values in target lesions were not significantly different but significantly higher in the surrounding normal prostatic tissue of the transition zone. CNR was comparable between ssEPI and rsEPI. Sensitivity and specificity were good for both sequences with 84/84% and 82/73% with a Youden selected cut-off of ADC = 0.971*10 mm/s for rsEPI and 1.017*10 mm/s for ssEPI. Anatomic artifacts were significantly less and SNR was lower on rsEPI compared to ssEPI in the subjective analysis.Delineation of the prostate shape was more accurate with rsEPI DWI than with ssEPI DWI with less anatomic artifacts and higher subjective SNR and image quality on rsEPI DW images. Diagnostic ability of quantitative ADC-values was not significantly different between the 2 sequences. Thus, rsEPI DWI might be more suitable for prostate MRI with regard to MRI-guided targeted biopsy and therapy planning.

Assessing the Clinical Value of Positive Multiparametric Magnetic Resonance Imaging in Young Men with a Suspicion of Prostate Cancer

BACKGROUND

There is a lack of evidence on the ability of magnetic resonance imaging (MRI) of the prostate to detect clinically significant prostate cancer (csPCa) in young patients.

OBJECTIVE

We hypothesised that the diagnostic performance of MRI for csPCa varies according to patient's age. To address this, we assessed the variation in the csPCa detection rate of MRI targeted biopsy (MRI-TBx) versus systematic random biopsy (SBx) across different patient ages.

DESIGN, SETTING, AND PARTICIPANTS

We retrospectively identified 930 patients who underwent prostate MRI and subsequent biopsy at two referral centres between 2013 and 2018. The Prostate Imaging Reporting and Data System (PI-RADS) was used for MRI reporting.

INTERVENTION

A lesion with a PI-RADS score of ≥3 detected at MRI received an MRI-TBx in addition to an SBx during the same session.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The outcome of our study was the relationship between age and csPCa detection rate at MRI-TBx and SBx, respectively. Clinically significant prostate cancer (PCa) was defined as the presence of PCa with Gleason score ≥3+4. Multivariable logistic regression analyses (MVAs) predicting csPCa detection were assessed for both MRI-TBx and SBx. Covariates were age, prostate-specific antigen density, PI-RADS score, previous biopsy status, digital rectal examination, and the number of targeted and systematic cores. The hypothesis that MRI accuracy in detecting csPCa differed by age was finally tested with a nonparametric loess analysis.

RESULTS AND LIMITATIONS

The overall rate of csPCa was 54% (n=506). Overall, 325 (35%) and 461 (50%) patients had csPCa at SBx and MRI-TBx, respectively. The median numbers of SBx and MRI-TBx cores were 12 (interquartile range [IQR]: 10-13) and 5 (IQR: 4-7), respectively. At MVA, age at biopsy was an independent predictor of csPCa at MRI-TBx only (odds ratio: 1.05), after accounting for confounders. In men aged less than roughly 50yr, SBx had a higher probability of detecting csPCa relative to MRI-TBx (25% vs 16% at 40yr). Conversely, in patients aged >50yr, the probability of csPCa was higher in MRI-TBx than in SBx, reaching the highest difference for very elderly patients (48% vs 68% at 80yr). The main limitations were the retrospective design and the small number of young patients.

CONCLUSIONS

In this study, we reported the performance of MRI and MRI-TBx in detecting csPCa changes according to patients' age.

PATIENT SUMMARY

In young patients, the performance of a systematic random biopsy in detecting clinically significant prostate cancer (csPCa) is higher relative to magnetic resonance imaging targeted biopsy (MRI-TBx), reflecting the lower accuracy of MRI in younger men. Conversely, in older patients, MRI-TBx showed a clinical benefit with a higher csPCa detection rate compared with SBx, suggesting an increase of MRI accuracy with the increase of age.

There Is No Way to Avoid Systematic Prostate Biopsies in Addition to Multiparametric Magnetic Resonance Imaging Targeted Biopsies

BACKGROUND

Whether or not adding systematic biopsies (transrectal ultrasound-guided biopsy [TRUS-Bx]) to targeted cores in patients with a lesion detected at multiparametric magnetic resonance imaging (mpMRI) is still a debated topic.

OBJECTIVE

To identify patients who can avoid TRUS-Bx at the time of mpMRI targeted biopsy (MRI-TBx) relying on individual patient probability to harbour clinically significant prostate cancer (csPCa) outside the index lesion (IL).

DESIGN, SETTING, AND PARTICIPANTS

A total of 339 European and 441 North American patients underwent fusion MRI-TBx and concomitant TRUS-Bx at two tertiary care referral centres between 2013 and 2017.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The study outcome was csPCa, defined as a Gleason score at biopsy of ≥7, outside the IL. Multivariable logistic regression analyses (MVAs) were performed to develop a predictive model for the study outcome. Multivariable-derived coefficients were used to develop a novel risk calculator in each cohort. The models were evaluated using the area under the curve (AUC), calibration plot, and decision-curve analyses.

RESULTS AND LIMITATIONS

In the European cohort, csPCa detection rate was 55%. The csPCa detection rate for TRUS-Bx was 41%. At MVAs, prostate volume, previous negative biopsy, and Prostate Imaging Reporting and Data System versions 4 and 5 were independent predictors for the presence of csPCa outside the IL. The multivariable model had an AUC of 0.78. Omitting TRUS-Bx in patients with a calculated risk of <15% would have spared 16% of TRUS-Bx at the cost of missing 7% of csPCa. Similar findings were obtained when the same analyses were performed in the North American cohort. No net benefit was observed for low-threshold probabilities (<15%) of the each model relative to the standard of care (performing TRUS-Bx in addition to MRI-TBx to all patients) in both cohorts. The study is limited by its retrospective design.

CONCLUSIONS

We failed to identify those patients who might safely benefit from MRI-TBx alone. The combination of MRI-TBx and TRUS-Bx should strongly be considered the best available approach.

PATIENT SUMMARY

In the presence of positive multiparametric magnetic resonance imaging (mpMRI) of the prostate, physicians should always perform systematic sampling of the prostate in addition to mpMRI targeted biopsy.

Magnetic resonance imaging-transrectal ultrasound fusion image-guided prostate biopsy: Current status of the cancer detection and the prospects of tailor-made medicine of the prostate cancer

Multi-parametric magnetic resonance imaging (mpMRI) has been increasingly used to diagnose clinically significant prostate cancer (csPCa) because of its growing availability and its ability to combine anatomical and functional data. Magnetic resonance imaging (MRI)-transrectal ultrasound (TRUS) fusion imaging provides MRI information with TRUS images for prostate biopsies. This technique combines the superior sensitivity of MRI for targeting suspicious lesions with the practicality and familiarity of TRUS. MRI-TRUS fusion image-guided prostate biopsy is performed with different types of image registration (rigid vs. elastic) and needle tracking methods (electromagnetic tracking vs. mechanical position encoders vs. image-based software tracking). A systematic review and meta-analysis showed that MRI-targeted biopsy detected csPCa at a significantly higher rate than did TRUS-guided biopsy, while it detected significantly fewer cases of insignificant PCas. In addition to the high accuracy of MRI-targeted biopsy for csPCa, localization of csPCa is accurate. The ability to choose the route of biopsy (transperineal vs. transrectal) is required, depending on the patients' risk and the location and size of suspicious lesions on mpMRI. Fusion image-guided prostate biopsy has the potential to allow precise management of prostate cancer, including active surveillance, radical treatment, and focal therapy.

Initial experience of magnetic resonance imaging/ultrasonography fusion transperineal biopsy: Biopsy techniques and results for 75 patients

Purpose

The aim of this study is to describe the technique and to report early results of transperineal magnetic resonance imaging and ultrasonography (MRI-US) fusion biopsy.

Materials and Methods

A total of 75 patients underwent MRI-US fusion transperineal biopsy. Targeted biopsy via MRI-US fusion imaging was carried out for cancer-suspicious lesions with additional systematic biopsy. Detection rates for overall and clinically significant prostate cancer (csPCa) were evaluated and compared between systematic and targeted biopsy. In addition, further investigation into the detection rate according to prostate imaging reporting and data system (PI-RADS) score was done. Results of repeat biopsies were also evaluated.

Results

Overall cancer detection rate was 61.3% (46 patients) and the detection rate for csPCa was 42.7% (32 patients). Overall detection rates for systematic and targeted biopsy were 41.3% and 57.3% (p<0.05), respectively. Detection rates for csPCa were 26.7% and 41.3%, respectively (p<0.05). The cancer detection rates via MRI fusion target biopsy were 30.8% in PI-RADS 3, 62.1% in PI-RADS 4 and 89.4% in PI-RADS 5. Rates of csPCa missed by targeted biopsy and systematic biopsy were 0.0% and 25.0%, respectively. The cancer detection rate in repeat biopsies was 61.1% (11 among 18 patients) in which 55.5% of cancer suspected lesions were located in the anterior portion.

Conclusions

Transperineal MRI-US fusion biopsy is useful for improving overall cancer detection rate and especially detection of csPCa. Transperineal MRI-US targeted biopsy show potential benefits to improve cancer detection rate in patients with high PI-RADS score, tumor located at the anterior portion and in repeat biopsies.

Current status and progress of focal therapy in Asia

PURPOSE OF REVIEW

With the increasing incidence of low-to-intermediate risk of prostate cancer (PCa) by the introduction of prostate-specific antigen (PSA) screening, focal therapy has become one of the promising treatment options in the world. In Asia, same movement are occurring using several technologies including cryoablation, high-intensity focused ultrasound, brachytherapy and irreversible electroporation. However, these are still not common strategies to treat organ-confined PCa. The purpose of this review is to summarize the most updated experience and future direction of focal therapy in Asian countries.

RECENT FINDINGS

The prevalence and diagnosis of PCa are increasing in Asian countries. This increase is related to various factors including the widespread implementation of PSA testing and lifestyle changes to more Westernized diets. With the increasing detection rate of early stage PCa, overdetection and overtreatment are recognized even in Asia. In this setting, accumulating data on multiparametric MRI and MRI-targeted biopsy as well as MRI-transrectal ultrasound (TRUS) fusion biopsy suggest the potential in improving the detection of clinically significant PCa in Asia. Furthermore, targeted focal therapy has emerged as a promising treatment strategy aiming for both providing oncological outcome and maintaining functional preservation in many Asian countries.

SUMMARY

At present, focal therapy is not a current standard choice for the treatment of localized PCa in Asian countries. However, with the increase of localized PCa and patient's preference for less invasive treatment with preservation of organ-function, focal therapy should become a definite treatment option for localized PCa in Asia.

Not All Multiparametric Magnetic Resonance Imaging-targeted Biopsies Are Equal: The Impact of the Type of Approach and Operator Expertise on the Detection of Clinically Significant Prostate Cancer

BACKGROUND

The extensive use of multiparametric magnetic resonance imaging (mpMRI) has led to an even more widespread use of different targeted biopsy techniques and approaches. The best way of performing targeted biopsies and the effect of operator expertise have still to be defined.

OBJECTIVE

To compare the rate of detection of clinically significant prostate cancer (csPCa) of different mpMRI targeted approaches and to assess the role of operator expertise in the detection of csPCa.

DESIGN, SETTING, AND PARTICIPANTS

We included 244 consecutive patients who underwent both 12-core transrectal ultrasound (TRUS) biopsy and mpMRI targeted biopsy with either a cognitive biopsy (CB) or fusion biopsy (FB) approach during the same session between 2013 and 2016 at a single tertiary referral centre.

INTERVENTION

All men underwent 1.5-T mpMRI with an endorectal coil. All biopsies were performed by three operators as their first cases of targeted biopsy. Lesions with a Prostate Imaging Recording and Data System (PI-RADS) v.2 score of ≥3 detected at mpMRI were targeted. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: csPCa was defined as disease with a Gleason score at biopsy of ≥7. Operator expertise was coded as the progressive number of targeted biopsies performed by each physician. Multivariable logistic regression analyses (MVA) were used to assess the association between the targeted biopsy technique (FB vs CB) and operator expertise for detection of csPCa. Covariates consisted of prostate-specific antigen, prostate volume, PI-RADS v.2 (3 vs >3), number of targeted cores per MRI lesion, and digital rectal examination (negative vs positive). The same analyses were performed for patients undergoing FB only after accounting for the FB approach (transrectal vs transperineal). A lowess smoothing weighted function was used to graphically assess the effect of operator expertise on the probability of detecting csPCa, after accounting for all confounders.

RESULTS AND LIMITATIONS

Overall, 157 patients (64%) underwent FB and 87 (36%) underwent CB. The overall csPCa detection rate was 58% for FB and 45% for CB (p=0.07). A significantly higher rate of csPCa detection in targeted samples was observed for FB compared to CB (57% vs 36%; p=0.002). On MVA, FB and operator expertise were significantly associated with a higher probability of csPCa detection in targeted samples (odds ratio [OR] 2.4 and 1.7, respectively; both p≤0.03). When the same analyses were repeated for patients undergoing FB, operator expertise remained an independent predictor of csPCa detection (OR 1.9; p=0.004). An increase in the probability of detecting csPCa with the number of procedures performed was observed after accounting for all confounders.

CONCLUSIONS

We demonstrated that FB had higher detection rate than CB for csPCa. Moreover, operator expertise was significantly associated with higher detection rates for csPCa.

PATIENT SUMMARY

When different targeted biopsy techniques were compared, fusion biopsy provided a higher detection rate compared to cognitive biopsy for clinically significant prostate cancer (csPCa). Moreover, we found that operator expertise was an important predictor of the detection of csPCa, regardless of the procedure used.

Technical Note: Error metrics for estimating the accuracy of needle/instrument placement during transperineal magnetic resonance/ultrasound-guided prostate interventions

PURPOSE

Image-guided systems that fuse magnetic resonance imaging (MRI) with three-dimensional (3D) ultrasound (US) images for performing targeted prostate needle biopsy and minimally invasive treatments for prostate cancer are of increasing clinical interest. To date, a wide range of different accuracy estimation procedures and error metrics have been reported, which makes comparing the performance of different systems difficult.

METHODS

A set of nine measures are presented to assess the accuracy of MRI-US image registration, needle positioning, needle guidance, and overall system error, with the aim of providing a methodology for estimating the accuracy of instrument placement using a MR/US-guided transperineal approach.

RESULTS

Using the SmartTarget fusion system, an MRI-US image alignment error was determined to be 2.0 ± 1.0 mm (mean ± SD), and an overall system instrument targeting error of 3.0 ± 1.2 mm. Three needle deployments for each target phantom lesion was found to result in a 100% lesion hit rate and a median predicted cancer core length of 5.2 mm.

CONCLUSIONS

The application of a comprehensive, unbiased validation assessment for MR/US guided systems can provide useful information on system performance for quality assurance and system comparison. Furthermore, such an analysis can be helpful in identifying relationships between these errors, providing insight into the technical behavior of these systems.

Targeted 11C-choline PET-CT/TRUS software fusion-guided prostate biopsy in men with persistently elevated PSA and negative mpMRI after previous negative biopsy

Background

We evaluated the feasibility and accuracy of 11C–choline PET-CT/TRUS fusion-guided prostate biopsy in men with persistently elevated PSA and negative mpMRI or contraindication to MRI, after previous negative biopsy. Clinical data were part of a prospective on-going observational clinical study: “Diagnostic accuracy of target mpMRI/US fusion biopsy in patients with suspected prostate cancer after initial negative biopsy”. Patients with a negative biopsy and negative mpMRI (PI-RADS v.2 < 3) or absolute contraindications to MRI and persistently elevated PSA, were included. All patients underwent 11C–choline PET with dedicated acquisition of the pelvis and PET-CT/TRUS-guided prostate biopsy by Bio-Jet™ fusion system (D&K Technologies, Germany). The primary endpoint was to assess the accuracy of 11C–choline PET-CT to determine the presence and the topographical distribution of PCa.

Results

Overall, 15 patients (median age 71 yrs. ± 8.89; tPSA 13.5 ng/ml ± 4.3) were analysed. Fourteen had a positive PET scan, which revealed 30 lesions. PCa was detected in 7/15 patients (46.7%) and four patients presented a clinically significant PCa: GS > 6. Over 58 cores, 25 (43.1%) were positive. No statistically significant difference in terms of mean and median values for SUVmax and SUVratio between benign and malignant lesions was found. PCa lesions with GS 3 + 3 (n = 3) showed a median SUVmax and SUVratio of 4.01 and 1.46, compared to 5.45 and 1.57, respectively for lesions with GS >6 (n = 4).

Conclusion

Software PET-CT/TRUS fusion-guided target biopsy could be a diagnostic alternative in patients with a suspected primary PCa and negative mpMRI, but its specificity appeared low.

[MRI/TRUS fusion-guided prostate biopsy : Value in the context of focal therapy]

BACKGROUND

Several systems for MRI/TRUS fusion-guided biopsy of the prostate are commercially available. Many studies have shown superiority of fusion systems for tumor detection and diagnostic quality compared to random biopsy. The benefit of fusion systems in focal therapy of prostate cancer (PC) is less clear.

OBJECTIVES

Critical considerations of fusion systems for planning and monitoring of focal therapy of PC were investigated.

MATERIALS AND METHODS

A systematic literature review of available fusion systems for the period 2013-5/2016 was performed. A checklist of technical details, suitability for special anatomic situations and suitability for focal therapy was established by the German working group for focal therapy (Arbeitskreis fokale und Mikrotherapie).

RESULTS

Eight fusion systems were considered (Artemis™, BioJet, BiopSee®, iSR´obot™ Mona Lisa, Hitachi HI-RVS, UroNav and Urostation®). Differences were found for biopsy mode (transrectal, perineal, both), fusion mode (elastic or rigid), navigation (image-based, electromagnetic sensor-based or mechanical sensor-based) and space requirements.

DISCUSSION

Several consensus groups recommend fusion systems for focal therapy. Useful features are "needle tracking" and compatibility between fusion system and treatment device (available for Artemis™, BiopSee® and Urostation® with Focal One®; BiopSee®, Hitachi HI-RVS with NanoKnife®; BioJet, BiopSee® with cryoablation, brachytherapy).

CONCLUSIONS

There are a few studies for treatment planning. However, studies on treatment monitoring after focal therapy are missing.

Evaluation of MRI/Ultrasound Fusion-Guided Prostate Biopsy Using Transrectal and Transperineal Approaches

Purpose

To evaluate transrectal (TR) and transperineal (TP) approaches for MRI/ultrasound (MRI/US) fusion-guided biopsy to detect prostate cancer (PCa).

Materials and Methods

154 men underwent multiparametric MRI and MRI/US fusion-guided biopsy between July 2012 and October 2016. 79/154 patients were biopsied with a TR approach and 75/154 with a TP approach. MRI was retrospectively analyzed according to PI-RADS version 2. PI-RADS scores were compared with histopathological results. Descriptive statistics, accuracy, and negative and positive predictive values were calculated. Histopathological results of first, second, and third MRI targeted biopsy cores were compared to evaluate the impact of one verus multiple targeted cores.

Results

Detection rates of PCa were 39% for TR biopsy and 75% for TP biopsy. Sensitivity/specificity for tumor detection with PI-RADS ≥ 4 were 81/69% for TR biopsy and 86/84% for TP biopsy. In 31% for TR biopsy and 19% for TP biopsy, PCa was found in the second or third MRI targeted biopsy core only.

Conclusion

MRI/US fusion-guided biopsy may be conducted with the TR as well as the TP approach with high accuracy, giving more flexibility for diagnosis and the option for focal treatment of PCa.

Multimodal Imaging in Focal Therapy Planning and Assessment in Primary Prostate Cancer

PURPOSE

There is increasing interest in focal therapy (male lumpectomy) of localized low-intermediate risk prostate cancer. Focal therapy is typically associated with low morbidity and provides the possibility of retreatment. Imaging is pivotal in stratification of men with localized prostate cancer for active surveillance, focal therapy or radical intervention. This article provides a concise review of focal therapy and the evolving role of imaging in this clinical setting.

METHODS

We performed a narrative and critical literature review by searching PubMed/Medline database from January 1997 to January 2017 for articles in the English language and the use of search keywords "focal therapy", "prostate cancer", and "imaging".

RESULTS

Most imaging studies are based on multiparametric magnetic resonance imaging. Transrectal ultrasound is inadequate independently but multiparametric ultrasound may provide new prospects. Positron emission tomography with radiotracers targeted to various underlying tumor biological features may provide unprecedented new opportunities. Multimodal Imaging appears most useful in localization of intraprostatic dominant index lesions amenable to focal therapy, in early assessment of therapeutic efficacy and potential need for additional focal treatments or transition to whole-gland therapy, and in predicting short-term and long-term outcomes.

CONCLUSION

Multimodal imaging is anticipated to play an increasing role in the focal therapy planning and assessment of low-intermediate risk prostate cancer and thereby moving this form of treatment option forward in the clinic.

Accuracy of real-time magnetic resonance imaging-transrectal ultrasound fusion image-guided transperineal target biopsy with needle tracking with a mechanical position-encoded stepper in detecting significant prostate cancer in biopsy-naïve men

OBJECTIVE

To evaluate the accuracy of real-time elastic fusion image-guided transperineal prostate biopsy with needle tracking involving a mechanical position-encoded stepper in detecting clinically significant prostate cancer for biopsy-naïve men.

METHODS

We prospectively recruited patients with serum prostate-specific antigen levels of 4.0-20 ng/mL and suspicious of prostate cancer on multiparametric magnetic resonance imaging. They underwent targeted biopsies for cancer-suspicious lesions and 12-core systematic biopsies. Pathological findings from biopsy cores and whole-mount specimens (for those who underwent radical prostatectomy) were analyzed.

RESULTS

A total of 250 patients were included, in whom targeted and systematic biopsies detected significant cancers in 55% and 25%, respectively (P < 0.001). The targeted biopsy cores (n = 527) showed significantly greater biopsy-proven significant cancer detection rates (P < 0.001), cancer core length (P < 0.0001), cancer core percentage (P < 0.001) and Gleason scores (P < 0.001) than did the systematic biopsies. The significant cancer detection rate for targeted lesions (those with Prostate Imaging and Reporting and Data System classification scores of 5) was 80%. Biopsy-proven significant cancer detection rates for targeted lesions ≤10 mm and >10 mm were similar for Prostate Imaging and Reporting and Data System scores of 4 (P = 0.707) and 5 (P = 0.386). In whole-mount specimens (n = 30), locations for 95% of significant cancers were diagnosed preoperatively. Targeted biopsies alone diagnosed 79% of significant cancers.

CONCLUSIONS

Although targeted biopsies are superior to systematic biopsies in detecting significant cancers, systematic biopsies maintain an important role in the diagnosis of prostate cancer in biopsy-naïve men.

Magnetic Resonance Imaging-Ultrasound Fusion-Guided Prostate Biopsy: Review of Technology, Techniques, and Outcomes

Transrectal ultrasound (TRUS)-guided (12-14 core) systematic biopsy of the prostate is the recommended standard for patients with suspicion of prostate cancer (PCa). Advances in imaging have led to the application of magnetic resonance imaging (MRI) for the detection of PCa with subsequent development of software-based co-registration allowing for the integration of MRI with real-time TRUS during prostate biopsy. A number of fusion-guided methods and platforms are now commercially available with common elements in image and analysis and planning. Implementation of fusion-guided prostate biopsy has now been proven to improve the detection of clinically significant PCa in appropriately selected patients.

Comparing Three Different Techniques for Magnetic Resonance Imaging-targeted Prostate Biopsies: A Systematic Review of In-bore versus Magnetic Resonance Imaging-transrectal Ultrasound fusion versus Cognitive Registration. Is There a Preferred Technique?

CONTEXT

The introduction of magnetic resonance imaging-guided biopsies (MRI-GB) has changed the paradigm concerning prostate biopsies. Three techniques of MRI-GB are available: (1) in-bore MRI target biopsy (MRI-TB), (2) MRI-transrectal ultrasound fusion (FUS-TB), and (3) cognitive registration (COG-TB).

OBJECTIVE

To evaluate whether MRI-GB has increased detection rates of (clinically significant) prostate cancer (PCa) compared with transrectal ultrasound-guided biopsy (TRUS-GB) in patients at risk for PCa, and which technique of MRI-GB has the highest detection rate of (clinically significant) PCa.

EVIDENCE ACQUISITION

We performed a literature search in PubMed, Embase, and CENTRAL databases. Studies were evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 checklist and START recommendations. The initial search identified 2562 studies and 43 were included in the meta-analysis.

EVIDENCE SYNTHESIS

Among the included studies 11 used MRI-TB, 17 used FUS-TB, 11 used COG-TB, and four used a combination of techniques. In 34 studies concurrent TRUS-GB was performed. There was no significant difference between MRI-GB (all techniques combined) and TRUS-GB for overall PCa detection (relative risk [RR] 0.97 [0.90-1.07]). MRI-GB had higher detection rates of clinically significant PCa (csPCa) compared with TRUS-GB (RR 1.16 [1.02-1.32]), and a lower yield of insignificant PCa (RR 0.47 [0.35-0.63]). There was a significant advantage (p = 0.02) of MRI-TB compared with COG-TB for overall PCa detection. For overall PCa detection there was no significant advantage of MRI-TB compared with FUS-TB (p=0.13), and neither for FUS-TB compared with COG-TB (p=0.11). For csPCa detection there was no significant advantage of any one technique of MRI-GB. The impact of lesion characteristics such as size and localisation could not be assessed.

CONCLUSIONS

MRI-GB had similar overall PCa detection rates compared with TRUS-GB, increased rates of csPCa, and decreased rates of insignificant PCa. MRI-TB has a superior overall PCa detection compared with COG-TB. FUS-TB and MRI-TB appear to have similar detection rates. Head-to-head comparisons of MRI-GB techniques are limited and are needed to confirm our findings.

PATIENT SUMMARY

Our review shows that magnetic resonance imaging-guided biopsy detects more clinically significant prostate cancer (PCa) and less insignificant PCa compared with systematic biopsy in men at risk for PCa.

Magnetic resonance imaging - ultrasound fusion targeted biopsy outperforms standard approaches in detecting prostate cancer: A meta-analysis

The aim of the present study was to determine whether magnetic resonance imaging - ultrasound (MRI-US) fusion prostate biopsy is superior to systematic biopsy for making a definitive diagnosis of prostate cancer. The two strategies were also compared regarding their ability to detect clinically significant and insignificant prostate cancer. A literature search was conducted through the PubMed, EMBASE and China National Knowledge Infrastructure databases using appropriate search terms. A total of 3,415 cases from 21 studies were included in the present meta-analysis. Data were expressed as relative risk (RR) and 95% confidence interval. The results revealed that MRI-US fusion biopsy achieved a higher rate of overall prostate cancer detection compared with systematic biopsy (RR=1.09; P=0.047). Moreover, MRI-US fusion biopsy detected more clinically significant cancers compared with systematic biopsy (RR=1.22; P<0.01). It is therefore recommended that multi-parametric MRI-US is performed in men suspected of having prostate cancer to optimize the detection of clinically significant disease, while reducing the burden of biopsies.

The value of magnetic resonance imaging and ultrasonography (MRI/US)-fusion biopsy platforms in prostate cancer detection: a systematic review

Despite limitations considering the presence, staging and aggressiveness of prostate cancer, ultrasonography (US)-guided systematic biopsies (SBs) are still the 'gold standard' for the diagnosis of prostate cancer. Recently, promising results have been published for targeted prostate biopsies (TBs) using magnetic resonance imaging (MRI) and ultrasonography (MRI/US)-fusion platforms. Different platforms are USA Food and Drug Administration registered and have, mostly subjective, strengths and weaknesses. To our knowledge, no systematic review exists that objectively compares prostate cancer detection rates between the different platforms available. To assess the value of the different MRI/US-fusion platforms in prostate cancer detection, we compared platform-guided TB with SB, and other ways of MRI TB (cognitive fusion or in-bore MR fusion). We performed a systematic review of well-designed prospective randomised and non-randomised trials in the English language published between 1 January 2004 and 17 February 2015, using PubMed, Embase and Cochrane Library databases. Search terms included: 'prostate cancer', 'MR/ultrasound(US) fusion' and 'targeted biopsies'. Extraction of articles was performed by two authors (M.G. and A.A.) and were evaluated by the other authors. Randomised and non-randomised prospective clinical trials comparing TB using MRI/US-fusion platforms and SB, or other ways of TB (cognitive fusion or MR in-bore fusion) were included. In all, 11 of 1865 studies met the inclusion criteria, involving seven different fusion platforms and 2626 patients: 1119 biopsy naïve, 1433 with prior negative biopsy, 50 not mentioned (either biopsy naïve or with prior negative biopsy) and 24 on active surveillance (who were disregarded). The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was used to assess the quality of included articles. No clear advantage of MRI/US fusion-guided TBs was seen for cancer detection rates (CDRs) of all prostate cancers. However, MRI/US fusion-guided TBs tended to give higher CDRs for clinically significant prostate cancers in our analysis. Important limitations of the present systematic review include: the limited number of included studies, lack of a general definition of 'clinically significant' prostate cancer, the heterogeneous study population, and a reference test with low sensitivity and specificity. Today, a limited number of prospective studies have reported the CDRs of fusion platforms. Although MRI/US-fusion TB has proved its value in men with prior negative biopsies, general use of this technique in diagnosing prostate cancer should only be performed after critical consideration. Before bringing MRI/US fusion-guided TB in to general practice, there is a need for more prospective studies on prostate cancer diagnosis.

Image-based monitoring of targeted biopsy-proven prostate cancer on active surveillance: 11-year experience

PURPOSE

To report our 11-year experience of Active Surveillance (AS) program focusing on modern transrectal ultrasound (TRUS)-based monitoring of targeted biopsy-proven cancer lesion.

METHODS

Consecutive patients on AS, who had targeted biopsy-proven lesion followed by at least a repeat surveillance biopsy and three times TRUS monitoring of the identical visible lesion, were included. Doppler grade of blood flow signal within the lesion was classified from grade 0 to 3. Biopsy-proven progression was defined as upgrade of Gleason score or 25% or greater increase in cancer core involvement.

RESULTS

Fifty patients were included in this study. Clinical variables (median) included age (61 years), clinical stage (T1c, 42;T2, 8), PSA (4.6 ng/ml), and Gleason score (3 + 3, n = 41;3 + 4, n = 9). Of the 50 patients, 34 demonstrated pathological progression at a median follow-up of 4.4 years. In comparing between without (n = 16) and with (n = 34) pathological progression, there were significant differences in cancer core involvement at entry (p = 0.003), the major axis diameter (p = 0.001) and minor axis diameter (p = 0.001) of the visible lesion at entry, increase in the major axis diameter (p = 0.005) and minor axis diameter (p = 0.013), and upgrade of Doppler grade (p < 0.0001). In multivariate analysis for predicting pathological progression, the increase (≥25%) in diameter of biopsy-proven lesion (hazard ratio, 15.314; p = 0.023) and upgrade of Doppler grade (hazard ratio, 37.409; p = 0.019) were significant risk factors.

CONCLUSIONS

Longitudinal monitoring of the TRUS-visible biopsy-proven cancer provides a new opportunity to perform per-lesion-based AS. The increase in diameter and upgrade of Doppler grade of the lesion were significant risk factors for biopsy-proven progression on AS.