Is an Extended 20-Core Prostate Biopsy Protocol More Efficient than the Standard 12-Core? A Randomized Multicenter Trial

Biopsy strategies in the era of mpMRI: a comprehensive review

BACKGROUND

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

METHOD

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

RESULTS

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

CONCLUSION

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

Performance of multi-parametric magnetic resonance imaging through PIRADS scoring system in biopsy naïve patients with suspicious prostate cancer

Background

Use of multi-parametric magnetic resonance imaging (mp-MRI) and Prostate Imaging Reporting and Data System (PI-RADS) scoring system allowed more precise detection of prostate cancer (PCa). Our study aimed at evaluating the diagnostic performance of mp-MRI in detection of PCa.

Methods

Eighty-six patients suspected to have prostate cancer were enrolled. All patients underwent mp-MRI followed by systematic and targeted trans-rectal ultrasound (TRUS) guided prostate biopsies. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of mp-MRI were evaluated.

Results

Forty-six patients (53.5%) had prostate cancer on targeted and systematic TRUS biopsies. On mp-MRI, 96.6% of lesions with PI-RADS < 3 revealed to be benign by TRUS biopsy, 73.3% of lesions with PI-RADS 4 showed ISUP grades ≥1, whereas all PI-RADS 5 lesions showed high ISUP grades ≥ 3. For PI-RADS 3 lesions, 62.5% of them revealed to be benign and 37.5% showed ISUP grades ≥1 by TRUS biopsy. PI-RADS scores ˃3 had 69.57% sensitivity and 85% specificity for detection of PCa. On adding the equivocal PI-RADS 3 lesions, PI-RADS scores ≥3 had higher sensitivity (97.83%), but at the cost of lower specificity (32.5%).

Conclusion

Mp-MRI using PI-RADS V2 scoring system categories ≤3 and >3 could help in detection of PCa. PI-RADS 3 lesions are equivocal. Including PI-RADS lesions ≥3 demonstrated higher sensitivity, but at the cost of lower specificity for mp-MRI in diagnosis for Pca.

Abbreviations

CDR: cancer detection rates; DRE: digital rectal examination; ISUP: international society of urological pathology; mp-MRI: multi-parametric magnetic resonance imaging; NPV: negative predictive value; PCa: prosatate cancer; PI-RADS: Prostate Imaging Reporting and Data System; PPV: Positive predictive value; PSA: prostate specific antigen; TRUS: transrectal ultrasound.

Use of increasing the number of biopsy cores in proportion to prostate size on prostate cancer diagnosis

Objectives:

This study aimed to determine the value of changing the number of biopsy cores in proportion to the size of the prostate in patients who had initial transperineal prostate biopsies.

Materials and methods:

This study included 470 patients who underwent an initial transperineal prostate biopsy. The number of biopsy cores was changed according to the value of the product of the vertical and horizontal diameters of the largest horizontal section of the prostate on transrectal ultrasonography (TRUS). Biopsies were classified into five groups: 12 cores, 14 cores, 18 cores, 20 cores, and 24 cores. Predictive factors for positive biopsy were studied with logistic regression analyses.

Results:

Variables that were significantly associated with positive biopsy were age, prostate-specific antigen density (PSAD), prostate volume (Pvol), and number of biopsy cores in univariate analysis. Age, PSAD, and Pvol were independent predictors in multivariate analysis. There was no significant difference in the number of biopsy cores, and it was not an independent predictor.

Conclusions:

Changing the number of biopsy cores according to the area of the largest horizontal section of the prostate on TRUS had no significant impact in detecting prostate cancer. However, further research is required to confirm this conclusion.

Level of evidence:

Level 2b.

Optimal Number of Systematic Biopsy Cores Used in Magnetic Resonance Imaging/Transrectal Ultrasound Fusion Targeted Prostate Biopsy

Background

In recent years, the effectiveness of magnetic resonance imaging (MRI)-ultrasound fusion targeted biopsy (MRF-TB) has been widely reported. In this study, we assessed the effect of reduction of the number of systematic biopsy (SB) cores on the cancer detection rate (CDR).

Methods

Patients with a high prostate-specific antigen (PSA) level underwent prostate MRI. The Prostate Imaging-Reporting and Data System version 2 (PI-RADS) was then used to rate the lesions. The inclusion criteria were as follows: (1) PSA level between 4.0 and 30.0 ng/mL and (2) patients with one or more lesions on MRI and a PI-RADS score of 3 or more. All enrolled patients were SB naïve or had a history of one or more prior negative SBs. A total of 104 Japanese met this selection criterion. We have traditionally performed 14-core SB following the MRF-TB. In this study, the CDRs of 10-core SB methods, excluding biopsy results at the center of the base and mid-level on both sides, were compared with those of the conventional biopsy method.

Results

We compared CDRs of the 14-core and 10-core SBs used in combination. The overall CDR was 55.8% for the former and 55.8% for the latter, thereby indicating that there was no significant difference (P = 1.00) between the two. In addition, the CDRs of csPCa were 51.9% for the former and 51.1% for the latter, which indicated that there was no significant difference (P = 0.317).

Conclusion

There was no significant difference in the CDR when the number of SB cores to be used in combination was 14 and 10.

Comparison of diagnostic efficacy between transrectal and transperineal prostate biopsy: A propensity score-matched study

This study compared the diagnostic efficacy of transrectal ultrasound (TRUS)-guided prostate biopsy (TRBx) and transperineal prostate biopsy (TPBx) in patients with suspected prostate cancer (PCa). We enrolled 2962 men who underwent transrectal (n = 1216) or transperineal (n = 1746) systematic 12-core prostate biopsy. Clinical data including age, prostate-specific antigen (PSA) level, and prostate volume (PV) were recorded. To minimize confounding, we performed propensity score-matching analysis. We measured and compared PCa detection rates between TRBx and TPBx, which were stratified by clinical characteristics and Gleason scores. The effects of clinical characteristics on PCa detection rate were assessed by logistic regression. For all patients, TPBx detected a higher proportion of clinically significant PCa (P < 0.001). Logistic regression analyses illustrated that PV had a smaller impact on PCa detection rate of TPBx compared with TRBx. Propensity score-matching analysis showed that the detection rates in TRBx were higher than those in TPBx for patients aged >- 80 years (80.4% vs 56.5%, P = 0.004) and with PSA level 20.1-100.0 ng ml^-1 (80.8% vs 69.1%, P = 0.040). In conclusion, TPBx was associated with a higher detection rate of clinically significant PCa than TRBx was; however, because of the high detection rate at certain ages and PSA levels, biopsy approaches should be optimized according to patents' clinical characteristics.

Impact of a novel ultrasound microvascular imaging and elastography on prostate cancer classification

Background

This study was aimed to compare the sensitivity of transrectal ultrasound (TRUS) guided systematic biopsy (TRUS-SB), superb microvascular imaging guided targeted biopsy (SMI-TB), and elastography ultrasound guided targeted biopsy (EU-TB) in detecting prostate cancer (PCa).

Methods

One hundred and eighty-four patients with suspicious PCa were randomly divided into two groups, SMI-TB group (n=92) and EU-TB group (n=92). All the patients received a 2-core SMI-TB or a 2-core EU-TB before receiving a 12-core TRU-SB depending on the group. The 2-core SMI-TB was conducted at the most increased vascularity areas rated by a radiologist on a semi-quantitative criterion. The 2-core EU-TB was performed at the dark blue areas that identified as suspicious areas. The PCa detection rate was compared among TRUS-SB, SMI-TB, and EU-TB in the total population and in two groups.

Results

PCa was detected in 65 out of 184 patients. The SMI-TB group patients received 1,272 cores in total with a positive rate of 23.81% (40/168) for SMI-TB cores and 4.17% (46/1,104) for TRUS-SB cores. The EU-TB group patients received a total of 1,262 cores with a positive rate of 31.01% (49/158) for EU-TB cores and 5.34% (59/1,104) for TRUS-SB cores. Targeted cores (27.30%, 89/326) achieved significantly higher sensitivity in PCa detection than systematic cores (4.76%, 105/2,208) (SMI-TB vs. TRUS-SB: OR 7.188, P<0.001; EU-TB vs. TRUS-SB: OR 7.962, P<0.001).

Conclusions

Superb microvascular imaging and elastography ultrasound guided targeted biopsy may result in higher prostate cancer detection rate as adjunct to gray-scale ultrasound guided systematic biopsy. However, targeted biopsy alone is not sufficient to detect PCa, compared with systematic biopsy.

The Role of Transrectal Ultrasound for Finding Focal Lesions in Prostate Cancer Detection Compared to Systematic Sextant Biopsy

OBJECTIVES

To evaluate the difference in cancer detection rate between targeted biopsy of focal lesions detected on transrectal ultrasound (TRUS) and systematic sextant biopsy.

MATERIALS AND METHODS

This retrospective study included patients who underwent TRUS-guided prostate biopsy between April 2014 and April 2017 and classified them into three groups: (1) sextant biopsy group patients underwent systematic sextant biopsy without evaluation of focal lesions on TRUS (n = 400), (2) focal lesion group patients underwent targeted biopsy for TRUS-detected lesions (n = 496), and (3) nonfocal lesion group patients had no TRUS-detected focal lesions (n = 222). Positive biopsy rates were compared using Chi-square tests between biopsy groups in all patients and two subgroups divided by prostate-specific antigen (PSA) level of 10 ng/mL.

RESULTS

The positive biopsy rate decreased in the order of the focal lesion group, the sextant biopsy group, and the nonfocal lesion group. All prostate cancers and prostate cancers with a Gleason score ≥7 were detected more frequently among patients with PSA ≤10 ng/mL in the focal lesion group than in the sextant biopsy group ( p = 0.008 and 0.007, respectively) and less frequently among patients with PSA >10 ng/mL in the nonfocal lesion group than in the sextant biopsy group ( p = 0.007 and 0.003, respectively).

CONCLUSION

In conclusion, searching focal lesion by TRUS is useful for improving the positive biopsy rate and risk stratification of PCa compared to systematic sextant biopsy without careful TRUS examination.

A randomised trial comparing two protocols for transrectal prostate repeat biopsy: six lateral posterior plus six anterior cores versus a standard posterior 12-core biopsy

Objective: To test the hypothesis that a combination of 6 posterior and 6 anterior cores detects more cancer than 12 posterior cores at a repeat transrectal prostate biopsy in men who have had one previous benign systematic biopsy.Patients and methods: Three hundred and forty men with persistently raised serum PSA were randomly allocated 1:1 to either a standard 12-core biopsy (12 cores from the lateral peripheral zone through a side-fire biopsy canal) or an experimental 12-core biopsy protocol with 6 anterior cores through an end-fire biopsy canal and 6 cores from the lateral peripheral zone through a side-fire biopsy canal. All biopsies were obtained transrectally with ultrasound guidance. The primary endpoint was cancer detection. Secondary endpoints were detection of ISUP Grade Groups/Gleason Grade Group ≥2 cancer, total biopsy cancer length and complications leading to medical intervention.Results: Prostate cancer was detected in 42/168 men (25%) in the experimental biopsy group and in 36/172 (21%) in the standard biopsy group (p = 0.44). The corresponding proportions for Gleason score ≥7 were 12% and 7% (p = 0.14). Median total cancer length was 4 (inter quartile range [IQR] = 1.5 - 6) mm in the end-fire group and 3 (IQR = 1.3 - 7) mm in the side-fire group. Ten men in the end-fire group and three in the side-fire group had a medical intervention for biopsy-related complications (p = 0.05).Conclusion: The biopsy protocol that included six end-fire anterior cores did not detect more cancer and was associated with more complications.Trial registration: ClinicalTrials.gov identifier: NCT02761135.

Decision models for distinguishing between clinically insignificant and significant tumors in prostate cancer biopsies: an application of Bayes' Theorem to reduce costs and improve outcomes

Prostate cancer is the second leading cause of death from cancer, behind lung cancer, for men in the U. S, with nearly 30,000 deaths per year. A key problem is the difficulty in distinguishing, after biopsy, between significant cancers that should be treated immediately and clinically insignificant tumors that should be monitored by active surveillance. Prostate cancer has been over-treated; a recent European randomized screening trial shows overtreatment rates of 40%. Overtreatment of insignificant tumors reduces quality of life, while delayed treatment of significant cancers increases the incidence of metastatic disease and death. We develop a decision analysis approach based on simulation and probability modeling. For a given prostate volume and number of biopsy needles, our rule is to treat if total length of cancer in needle cores exceeds c, the cutoff value, with active surveillance otherwise, provided pathology is favorable. We determine the optimal cutoff value, c*. There are two misclassification costs: treating a minimal tumor and not treating a small or medium tumor (large tumors were never misclassified in our simulations). Bayes' Theorem is used to predict the probabilities of minimal, small, medium, and large cancers given the total length of cancer found in biopsy cores. A 20 needle biopsy in conjunction with our new decision analysis approach significantly reduces the expected loss associated with a patient in our target population about to undergo a biopsy. Longer needles reduce expected loss. Increasing the number of biopsy cores from the current norm of 10-12 to about 20, in conjunction with our new decision model, should substantially improve the ability to distinguish minimal from significant prostate cancer by minimizing the expected loss from over-treating minimal tumors and delaying treatment of significant cancers.

Update on Strategies to Reduce Infectious Complications After Prostate Biopsy

CONTEXT

Prostate biopsy is one of the most performed procedures in urology. As a diagnostic procedure it should be of low risk. However, morbidity following prostate biopsy is common due to infectious complications.

OBJECTIVE

To describe how to reduce infectious complications following prostate biopsy. We report on antibiotic and technical interventions to reduce infectious complications.

EVIDENCE ACQUISITION

The data presented are based on a narrative review. Search in PubMed and Medline was performed until May 2018 with a focus on randomised controlled trials and meta-analyses. Articles were reviewed for data on symptomatic infections, hospitalisation, and adverse events.

EVIDENCE SYNTHESIS

Antibiotic prophylaxis is the standard of care. However, the duration of antibiotic preemptive treatment is still under debate. The use of augmented antibiotic prophylaxis as well as targeted antibiotic prophylaxis might be of potential value, but evidence is currently limited. Moreover, no antibiotic class was shown to be clearly superior to another. The evaluation of the technical aspects during prostate biopsy reveals that rectal preparation with povidone-iodine is clearly effective to reduce infectious complications. Transperineal biopsy has a potential benefit to reduce infectious complications, but powerful randomised controlled studies are missing. Finally, the number of biopsy cores, the application of periprostatic nerve block, or the use of a cleansing enema has no impact on prostate biopsy in terms of infectious complications.

CONCLUSIONS

The available data only suggest that rectal preparation with povidone-iodine as well as antibiotic prophylaxis is of significant advantage to reduce infectious complications following prostate biopsy. The augmented and targeted antibiotic prophylaxis shows some potential, but need further validation.

PATIENT SUMMARY

In this review we evaluate the best management strategy to prevent infectious complications following prostate biopsy. We show that antibiotic prophylaxis is essential for prostate biopsy and that rectal preparation with povidone-iodine is mandatory.

Quality indicators of clinical cancer care for prostate cancer: a population-based study in southern Switzerland

Background

Quality of cancer care (QoCC) has become an important item for providers, regulators and purchasers of care worldwide. Aim of this study is to present the results of some evidence-based quality indicators (QI) for prostate cancer (PC) at the population-based level and to compare the outcomes with data available in the literature.

Methods

The study included all PC diagnosed on a three years period analysis (01.01.2011–31.12.2013) in the population of Canton Ticino (Southern Switzerland) extracted from the Ticino Cancer Registry database. 13 QI, approved through the validated Delphi methodology, were calculated using the “available case” approach: 2 for diagnosis, 4 for pathology, 6 for treatment and 1 for outcome. The selection of the computed QI was based on the availability of medical documentation. QI are presented as proportion (%) with the corresponding 95% confidence interval.

Results

700 PC were detected during the three-year period 2011–2013: 78.3% of them were diagnosed through a prostatic biopsy and for 72.5% 8 or more biopsy cores were taken. 46.5% of the low risk PC patients underwent active surveillance, while 69.2% of high risk PC underwent a radical treatment (radical prostatectomy, radiotherapy or brachytherapy) and 73.5% of patients with metastatic PC were treated with hormonal therapy. The overall 30-day postoperative mortality was 0.5%.

Conclusions

Results emerging from this study on the QoCC for PC in Canton Ticino are encouraging: the choice of treatment modalities seems to respect the international guidelines and our results are comparable to the scarce number of available international studies. Additional national and international standardisation of the QI and further QI population-based studies are needed in order to get a real picture of the PC diagnostic-therapeutic process progress through the definition of thresholds of minimal standard of care.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4604-2) contains supplementary material, which is available to authorized users.

[Prostate cancer diagnostic by saturation randomized biopsy versus rigid targeted biopsy]

INTRODUCTION

Optimal diagram teaming up randomized biopsy (BR) to targeted biopsy (BC) is still missing for the diagnostic of prostate cancer (CP). This study compares diagram of 6, 12 or 18 BR with or without BC rigid.

METHODS

Between January 2014 and May 2016, 120 patients had prostate biopsy BR and BC. Each patient had 18 BR and BC. Results compared sextant (6 BR), standard (12 BR) and saturation (18 BR) protocol with or without the adding of BC for the detection of CP.

RESULTS

Rectal examination was normal, mean PSA at 8.99ng/mL and mean volume at 54cm³. It was first round for 48% of patients. Forty-four cancers were found by the group 18 BR+BC (control). The detection rate was respectively, for 6, 12 and 18 BR of 61%, 82% and 91%. The add of BC increased this detection of +27% for 6 BR+BC, +13% for 12 BR+BC and +9% for 18 BR+BC. BC found 70% of all CP. Nine percent of CP were missed by BR only. Significant CP (Gleason≥7) diagnostic was the same for 12 BR+BC and 18 BR+BC.

CONCLUSION

The add of BC to BR increase the detection of CP by 10%. Twelve BR+BC is the optimal diagram for the diagnostic of CP finding 95% of CP and 97% of significant CP.

LEVEL OF EVIDENCE

4.

Defining Novel and Practical Metrics to Assess the Deliverables of Multiparametric Magnetic Resonance Imaging/Ultrasound Fusion Prostate Biopsy

PURPOSE

Multiparametric magnetic resonance/ultrasound targeted prostate biopsy is touted as a tool to improve prostate cancer care and yet its true clinical usefulness over transrectal ultrasound guided prostate biopsy has not been systematically analyzed. We introduce 2 metrics to better quantify and report the deliverables of targeted biopsy.

MATERIALS AND METHODS

We reviewed our prospective database of patients who underwent simultaneous multiparametric magnetic resonance/ultrasound targeted prostate biopsy and transrectal ultrasound guided prostate biopsy. Actionable intelligence metric was defined as the proportion of patients in whom targeted biopsy provided actionable information over transrectal ultrasound guided prostate biopsy. Reduction metric was defined as the proportion of men in whom transrectal ultrasound guided prostate biopsy could have been omitted. We compared metrics in our cohort with those in prior reports.

RESULTS

A total of 371 men were included in study. The actionable intelligence and reduction metrics were 22.2% and 83.6% in biopsy naïve cases, 26.7% and 84.2% in prior negative transrectal ultrasound guided prostate biopsy cases, and 24% and 77.5%, respectively, in active surveillance cases. No significant differences were observed among the groups in the actionable intelligence metric and the reduction metric (p = 0.89 and 0.27, respectively). The actionable intelligence metric was 25.0% for PI-RADS™ (Prostate Imaging Reporting and Data System) 3, 27.5% for PI-RADS 4 and 21.7% for PI-RADS 5 lesions (p = 0.73). Transrectal ultrasound guided prostate biopsy could have been avoided in more patients with PI-RADS 3 compared to PI-RADS 4/5 lesions (reduction metric 92.0% vs 76.7%, p <0.01). Our results compare favorably to those of other reported series.

CONCLUSIONS

The actionable intelligence metric and the reduction metric are novel, clinically relevant quantification metrics to standardize the reporting of multiparametric magnetic resonance/ultrasound targeted prostate biopsy deliverables. Targeted biopsy provides actionable information in about 25% of men. Reduction metric assessment highlights that transrectal ultrasound guided prostate biopsy may only be omitted after carefully considering the risk of missing clinically significant cancers.

Prostate cancer detection on transrectal ultrasonography-guided random biopsy despite negative real-time magnetic resonance imaging/ultrasonography fusion-guided targeted biopsy: reasons for targeted biopsy failure

OBJECTIVE

To examine the value of additional transrectal ultrasonography (TRUS)-guided random biopsy (RB) in patients with negative magnetic resonance imaging (MRI)/ultrasonography (US) fusion-guided targeted biopsy (TB) and to identify possible reasons for TB failure.

PATIENTS AND METHODS

We conducted a subgroup analysis of 61 men with prostate cancer (PCa) detected by 10-core RB but with a negative TB, from a cohort of 408 men with suspicious multiparametric magnetic resonance imaging (mpMRI) between January 2012 and January 2015. A consensus re-reading of mpMRI results (using Prostate Imaging Reporting and Data System [PI-RADS] versions 1 and 2) for each suspicious lesion was performed, with the image reader blinded to the biopsy results, followed by an unblinded anatomical correlation of the lesion on mpMRI to the biopsy result. The potential reasons for TB failure were estimated for each lesion. We defined clinically significant PCa according to the Epstein criteria and stratified patients into risk groups according to the European Association of Urology guidelines.

RESULTS

Our analysis showed that RB detected significant PCa in 64% of patients (39/61) and intermediate-/high-risk PCa in 57% of patients (35/61). The initial mpMRI reading identified 90 suspicious lesions in the cohort. Blinded consensus re-reading of the mpMRI led to PI-RADS score downgrading of 45 lesions (50%) and upgrading of 13 lesions (14%); thus, negative TB could be explained by falsely high initial PI-RADS scores for 32 lesions (34%) and sampling of the target lesion by RB in the corresponding anatomical site for 36 out of 90 lesions (40%) in 35 of 61 patients (57%). Sampling of the target lesion by RB was most likely for lesions with PI-RADS scores of 4/5 and Gleason scores (GS) of ≥7. A total of 70 PCa lesions (67% with GS 6) in 44 patients (72%) were sampled from prostatic sites with no abnormalities on mpMRI.

CONCLUSION

In cases of TB failure, RB still detected a high rate of significant PCa. The main reason for a negative TB was a TB error, compensated for by positive sampling of the target lesion by the additional RB, and the second reason for TB failure was a falsely high initial PI-RADS score. The challenges that arise for both MRI diagnostics and prostate lesion sampling are evident in our data and support the integration of RB into the TB workflow.

Transperineal template prostate-mapping biopsies: an evaluation of different protocols in the detection of clinically significant prostate cancer

OBJECTIVES

To determine whether modified transperineal template prostate-mapping (TTPM) biopsy protocols, altering the template or the biopsy density, have sensitivity and negative predictive value (NPV) equal to full 5-mm TTPM.

PATIENTS AND METHODS

Retrospective analysis of an institutional registry including treatment-naïve men undergoing 5-mm TTPM biopsy analysed in a 20-zone fashion. The value of three modified strategies was assessed by comparing the information provided by selected zones against full 5-mm TTPM. Strategy 1, did not consider the findings of anterior areas; strategies 2 and 3 simulated a reduced biopsy density by excluding intervening zones. A bootstrapping technique was used to calculate reliable estimates of sensitivity and NPV of these three strategies for the detection of clinically significant disease (maximum cancer core length ≥4 mm and/or Gleason score ≥3 + 4).

RESULTS

In all, 391 men with a median (interquartile range, IQR) age of 62 (58-67) years were included. The median (IQR) PSA level and PSA density were 6.9 (4.8-10) ng/mL and 0.17 (IQR 0.12-0.25) ng/mL/mL, respectively. A median (IQR) of 6 (2-9) cores out of 48 (33-63) taken per man were positive for prostate cancer. No cancer was detected in 67 men (17%), whilst low-, intermediate- and high-risk disease was identified in 78 (20%), 80 (21%), and 166 (42%), respectively. Strategy 1, 2 and 3 had sensitivities of 78% [95% confidence interval (CI) 73-84%], 85% (95% CI 80-90%) and 84% (95% CI 79-89%), respectively. The NPVs of the three strategies were 73% (95% CI 67-80%), 80% (95% CI 74-86%) and 79% (95% CI 72-84%), respectively.

CONCLUSION

Altering the template or decreasing sampling density has a substantial negative impact on the ability of TTPM biopsy to exclude clinically significant disease. This should be considered when modified TTPM biopsy strategies are used to select men for tissue-preserving approaches, and when modified TTPM are used to validate new diagnostic tests.

Approaches for Initial Prostate Biopsy and Antibiotic Prophylaxis

CONTEXT

Debate on the optimal technique to use as an initial prostate biopsy (PB) strategy is continually evolving.

OBJECTIVE

To review recent advances and current recommendations regarding initial PB and antibiotic prophylaxis.

EVIDENCE ACQUISITION

A nonsystematic review of the literature was performed up to October 2014 using the PubMed and Embase databases. Articles were selected with preference for the highest level of evidence in publications within the past 5 yr.

EVIDENCE SYNTHESIS

The decision to perform PB is still based on an abnormal digital rectal examination or increased prostate0specific antigen (PSA) level without clear consensus about the absolute cutoff. Several biomarkers have been suggested to improve PSA-based PB decision-making and minimize overdiagnosis and overtreatment. The random 12-core transrectal (TR) ultrasound-guided approach remains the standard-of-care technique for PB. A >12-core scheme may be considered as an alternative in a single patient given his clinical features (large volume, low PSA levels). Transperineal biopsies may only be considered as an alternative to the TR route in special situations. Nevertheless, given the increase in antimicrobial resistance, the impact on the post-biopsy sepsis rate should be assessed in well-designed clinical trials. Imaging-guided targeted PB strategies, combined or not with random PBs, may represent the future of prostate cancer diagnosis by reducing the number of PBs and improving decision-making.

CONCLUSIONS

The 12-core TR scheme remains the standard of care for initial PB. The actual trend for PB strategy, with the aim of avoiding overdiagnosis of very low-risk cancers, could rapidly change our current indications and techniques through new biomarkers and imaging-guided targeted strategies. Nevertheless, the cost-benefit balance of these techniques should be closely assessed in the setting of initial PB strategy.

PATIENT SUMMARY

This review highlights current recommendations for prostate biopsy and possible advances in the near future.

Short-term prophylaxis with ciprofloxacin in extended 16-core prostate biopsy

Objective

To evaluate the safety, efficacy and possible complications of 16-core transrectal prostate biopsies using two doses of ciprofloxacin for prophylaxis of infectious complications.

Materials and Methods

Sixteen-core prostate biopsies were performed on a number of patients with different signs of potential prostate cancer. Complications were assessed both during the procedure and one week later. After the procedure, urine samples were collected for culture. The rate of post-biopsy complications, hospital visits and hospitalizations were also analyzed. Ciprofloxacin (500 mg) was administered two hours before, and eight hours after the procedure.

Results

The overall rate of post-biopsy complications was 87.32%, being 5.4% of those considered major complications due to hemorrhage, or to urinary retention. Eight patients required hospital treatment post-biopsy. Fever occurred in just one patient (0.29%). There was no incidence of orchitis, epididymitis, prostatitis, septicemia, hospitalization, or death. The urine culture showed positive results in five patients (2.15%).

Conclusion

One-day prophylaxis with ciprofloxacin proved to be safe and effective in the prevention of infectious complications following 16-core prostate biopsies.

The detection of significant prostate cancer is correlated with the Prostate Imaging Reporting and Data System (PI-RADS) in MRI/transrectal ultrasound fusion biopsy

PURPOSE

To evaluate the performance of real-time MRI/ultrasound (MRI/US) fusion-guided targeted biopsy (TB) in men with primary and repeat biopsies and correlate the prostate cancer detection rate (CDR) with the PI-RADS score.

METHODS

Analysis included 408 consecutive men with primary and prior negative biopsies who underwent TB and 10-core random biopsy (RB) between January 2012 and January 2015. TB was performed with a real-time MRI/US fusion platform with sensor-based registration. Clinically significant PCa was defined as Gleason score (GS) ≥ 7 or GS 6 with maximal cancer core length ≥ 4 mm for TB and according to Epstein criteria for RB.

RESULTS

The overall CDR was 56 % (227/408). The CDR for primary biopsy was 74 % (60/81) and 57 % (67/117), 49 % (62/126), 45 % (38/84) for patients with 1, 2 and ≥ 3 prior negative biopsies. CDRs correlated with PI-RADS 2/3/4/5 were 16 % (5/32), 26 % (29/113), 62 % (94/152) and 89 % (99/111), respectively. The rates of significant tumors in relation to PI-RADS 2/3/4/5 were 60 % (3/5), 66 % (19/29), 74 % (70/94), 95 % (94/99). In 139 (61 %) cases with radical prostatectomy (RP), the rates of ≥ pT3 tumors in correlation with PI-RADS 4 and 5 were 20 % (11/56) and 49 % (32/65). PI-RADS constituted the strongest predictor of significant PCa detection (p < 0.007).

CONCLUSIONS

Real-time MRI/US fusion-guided TB combined with RB improved PCa detection in patients with primary and repeat biopsies. The CDR was strongly correlated with a rising PI-RADS score, values of 4 and 5 increasing the detection of clinically significant tumors and leading to a higher histological stage after RP.

The diagnostic ability of an additional midline peripheral zone biopsy in transrectal ultrasonography-guided 12-core prostate biopsy to detect midline prostate cancer

Purpose:

The goal of this study was to evaluate the diagnostic effect of adding a midline peripheral zone (PZ) biopsy to the 12-core biopsy protocol used to diagnose prostate cancer (PC), and to assess the clinical and pathologic characteristics of midline-positive PC in order to identify a potential subgroup of patients who would require midline PZ biopsy.

Methods:

This study included 741 consecutive patients who underwent a transrectal ultrasonography-guided, 12-core prostate biopsy with an additional midline core biopsy between October 2012 and December 2013. We grouped patients by the presence or absence of PC and subdivided patients with PC based on the involvement of the midline core. The clinical characteristics of these groups were compared, including serum prostate-specific antigen (PSA) concentrations, PSA density, and pathological features in the biopsy specimens.

Results:

PC was detected in 289 patients (39.0%). Among the PC patients, 66 patients (22.8%) had midline PC. No patients were diagnosed with PC based only on a midline core. The Gleason scores, number of positive cores, tumor core length, serum PSA concentrations, and PSA density were significantly higher in patients with midline-positive PC (P<0.001). Furthermore, significant cancer was more frequent in the midline-positive group (98.5% vs. 78.0%).

Conclusion:

Patients showing a positive result for PC in a midline PZ biopsy were more likely to have multiple tumors or large-volume PC with a high tumor burden. However, our data indicated that an additional midline core biopsy is unlikely to be helpful in detecting occult midline PC.

Accuracy of Magnetic Resonance Imaging/Ultrasound Fusion Targeted Biopsies to Diagnose Clinically Significant Prostate Cancer in Enlarged Compared to Smaller Prostates

PURPOSE

We assessed the accuracy of magnetic resonance imaging/transrectal ultrasound fusion biopsies to diagnose prostate cancer according to gland size.

MATERIALS AND METHODS

A prospective study was performed in 232 men with a first round biopsy, multiparametric magnetic resonance imaging with a lesion, a Likert score of 2 or greater and prostate specific antigen less than 10 ng/ml. All men underwent a standard 12-core protocol plus a protocol of 2 or 3 targeted cores. Significant prostate cancer was defined as at least 1 core with a Gleason score of 7 (3 + 4) or 6 with a greater than 4 mm maximal cancer core length.

RESULTS

Mean ± SD patient age was 64 ± 6.4 years, mean prostate specific antigen was 6.65 ± 1.8 ng/ml and mean prostate volume was 40 ± 24.3 ml. The overall detection rate of clinically significant prostate cancer was 44%. The detection rate of clinically significant prostate cancer by magnetic resonance imaging-transrectal ultrasound fusion guided biopsy was 77% for prostate glands less than 30 cm(3), and 61%, 47% and 34% for glands 30 to less than 38.5, 38.5 to less than 55 and 55 to 160 cm(3), respectively (p = 0.001). Differences in prostate cancer detection rates between the standard and targeted protocols were not significant for patients with a prostate volume of 40 cm(3) or less (p = 0.8). Conversely 12 patients with a prostate volume greater than 40 cm(3) had clinically significant prostate cancer using the targeted but not the standard protocol and in 3 prostate cancer was detected by the standard but not the targeted protocol (p = 0.04).

CONCLUSIONS

Magnetic resonance imaging-transrectal ultrasound fusion biopsies increased the yield of first round prostate biopsies in patients with a prostate volume greater than 40 cm(3).

Length of prostate biopsies is not necessarily compromised by pooling multiple cores in one paraffin block: an observational study

Background

Individually submitted prostatic needle biopsies are recommended by most guidelines because of their potential advantage in terms of core quality. However, unspecified bilateral biopsies are commonly submitted in many centers. The length of the core is the key quality indicator of prostate biopsies. Because there are few recent publications comparing the quality of 12 site-designated biopsies versus pooled biopsies, we compared the lengths of the biopsies obtained by both methods.

Methods

The material was obtained from 471 consecutive subjects who underwent prostatic needle biopsy in the Tampere University Hospital district between January and June 2013. Biopsies from 344 subjects fulfilled the inclusion criteria. The total number of cores obtained was 4047. The core lengths were measured on microscope slides. Extraprostatic tissue was subtracted from the core length.

Results

The aggregate lengths observed were 129.5 ± 21.8 mm (mean ± SD) for site-designated cores and 136.9 ± 26.4 mm for pooled cores (p = 0.09). The length of the core was 10.8 ± 1.8 mm for site-designated cores and 11.4 ± 2.2 mm for pooled cores (p = 0.87). The median length for pooled cores was 11 mm (range 5 mm – 18 mm). For individual site-designated cores, the median length was 11 mm (range 7 mm −15 mm). The core length was not correlated with the number of cores embedded into one paraffin block (r = 0.015). There was no significant difference in cancer detection rate (p = 0.62).

Conclusions

Our results suggest that unspecified bilateral biopsies do not automatically lead to reduced core length. We conclude that carefully embedded multiple (three to nine) cores per block may yield cores of equal quality in a more cost-efficient way and that current guidelines favoring individually submitted cores may be too strict.

PTEN loss is associated with upgrading of prostate cancer from biopsy to radical prostatectomy

When distinguishing between indolent and potentially harmful prostate cancers, the Gleason score is the most important variable, but may be inaccurate in biopsies due to tumor under-sampling. This study investigated whether a molecular feature, PTEN protein loss, could help identify which Gleason score 6 tumors on biopsy are likely to be upgraded at radical prostatectomy. Seventy one patients with Gleason score 6 tumors on biopsy upgraded to Gleason score 7 or higher at prostatectomy (cases) were compared with 103 patients with Gleason score 6 on both biopsy and prostatectomy (controls). A validated immunohistochemical assay for PTEN was performed, followed by fluorescence in situ hybridization (FISH) to detect PTEN gene deletion in a subset. PTEN protein loss and clinical-pathologic variables were assessed by logistic regression. Upgraded patients were older than controls (61.8 vs 59.3 years), had higher pre-operative PSA levels (6.5 vs 5.3 ng/ml) and a higher fraction of involved cores (0.42 vs 0.36). PTEN loss by immunohistochemistry was found in 18% (13/71) of upgraded cases compared with 7% (7/103) of controls (P=0.02). Comparison between PTEN immunohistochemistry and PTEN FISH showed the assays were highly concordant, with 97% (65/67) of evaluated biopsies with intact PTEN protein lacking PTEN gene deletion, and 81% (13/16) of the biopsies with PTEN protein loss showing homozygous PTEN gene deletion. Tumors with PTEN protein loss were more likely to be upgraded at radical prostatectomy than those without loss, even after adjusting for age, preoperative PSA, clinical stage and race (odds ratio=3.04 (1.08-8.55; P=0.035)). PTEN loss in Gleason score 6 biopsies identifies a subset of prostate tumors at increased risk of upgrading at radical prostatectomy. These data provide evidence that a genetic event can improve Gleason score accuracy and highlight a path toward the clinical use of molecular markers to augment pathologic grading.

First round of targeted biopsies using magnetic resonance imaging/ultrasonography fusion compared with conventional transrectal ultrasonography-guided biopsies for the diagnosis of localised prostate cancer

OBJECTIVES

To assess the accuracy of magnetic resonance imaging (MRI)/transrectal ultrasonography (TRUS) fusion to guide first-round biopsies in the diagnosis of localised prostate cancer (PCa) in men with a prostate-specific antigen (PSA) ≤10 ng/mL.

PATIENTS AND METHODS

A prospective study was conducted on men who met the following criteria: first-round biopsy, multiparametric MRI (mpMRI) showing a lesion with a Likert score ≥2 and a PSA <10 ng/mL. All men underwent a extended 12-core protocol plus a protocol of two or three targeted cores on the mpMRI index lesion. The UroStation (Koelis, Grenoble, France) and a V10 ultrasound system with an end-fire three-dimensional TRUS transducer were used for the fusion imaging procedure. Significant PCa was defined as: at least one core with a Gleason score of 3 + 4 or 6 with a maximum cancer core length ≥4 mm.

RESULTS

A total of 152 men, whose median PSA level was 6 ng/mL, were included in the study. The proportion of positive cores was significantly higher with the targeted-core protocol than with the extended 12-core protocol (P < 0.001). The proportion of men with clinically significant PCa was higher with the targeted-core protocol than with the extended 12-core protocol (P = 0.03). The proportion of patients having at least one positive biopsy (targeted-core protocol) was significantly different among the Likert score categories (P < 0.001).

CONCLUSIONS

For the first round of biopsies, MRI/TRUS-fusion targeted biopsies detected more men with clinically significant PCa than did standard extended 12-core biopsy alone.