Saturation technique does not improve cancer detection as an initial prostate biopsy strategy

Discrepancies in Gleason score between needle core biopsy and radical prostatectomy specimens with correlation between clinical and pathological staging

BACKGROUND

The studies have shown that GS given after assessment of the entire prostate gland on the radical prostatectomy specimen may differ from GS given after examination of a small sample from needle core biopsy. We conducted this study to assess discrepancies in the Gleason score between NCB and RP specimens and to find out the correlation between the clinical stage and pathological stage.

METHODS

The study included 174 patients with carcinoma prostate which underwent robotic-assisted radical prostatectomy (RARP). Pre-operative Gleason score was determined on 12-core biopsy samples under trans-rectal ultrasound (TRUS) guidance. The Gleason score obtained from the radical prostatectomy specimen was compared with that of the NCB Gleason score to find out differences.

RESULTS

The preoperative Gleason score (GS) ranges from 6 to 9 with a mean GS of 6.97 ± 1.02. The post-operative GS ranges between 6 and 10 with mean and GS of 7.5 ± 1.10. On the pre-operative assessment of biopsy specimens, 70 (43.2%) patients had a GS of 6, while 44 patients had a GS of 7 (27.1%) and 48 (29.8%) patients had a GS of more than 7. On the postoperative assessment of specimens, 31 (19.1%) patients had post-operative GS of 6, while 66 (41%) patients had GS of 7 and 74 (41.1%) patients had GS of more than 7. When pre-operative GS and post-operative GS were compared, no changes were observed in the GS of 79 patients, whereas 83 patients showed the difference in GS, with 75 patients showing up-gradation and eight patients marked as down-graded.

CONCLUSION

concordance between biopsy and the pathology results directly affects the prognosis of the patient. The results of our study demonstrated the rate of discordance between Gleason scores obtained from transrectal prostate biopsy and RP surgical specimens. This rate brings into question the accuracy of the chosen treatment.

Role of targeted biopsy, perilesional biopsy, random biopsy, and their combination in the detection of clinically significant prostate cancer by mpMRI/transrectal ultrasonography fusion biopsy in confirmatory biopsy during active surveillance program

BACKGROUND

Based on the findings of different trials in biopsy naïve patients, target biopsy (TB) plus random biopsy (RB) during mpMRI-guided transrectal ultrasound fusion biopsy (FB) are often also adopted for the biopsy performed during active surveillance (AS) programs. At the moment, a clear consensus on the extent and modalities of the procedure is lacking.

OBJECTIVE

To evaluate the increase in diagnostic accuracy achieved by perilesional biopsy (PL) and different RB schemes during FB performed in AS protocol.

DESIGN, SETTING, AND PARTICIPANTS

We collected prospectively the data of 112 consecutive patients with low- or very-low-risk prostate cancer; positive mpMRI underwent biopsy at a single academic institution in the context of an AS protocol.

INTERVENTION(S)

mpMRI/transrectal US FB with Hitachi RVS system with 3 TB and concurrent transrectal 24-core RB.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The diagnostic yield of the different possible biopsy schemes (TB only; TB + 4 perilesional (PL) cores; TB + 12-core RB; TB + 24-core RB) was compared by the McNemar test. Univariable and multivariable regression analyses were adopted to identify predictors of any cancer, Gleason grade group (GGG) ≥2 cancers, and the presence of GGG≥2 cancers in the larger schemes only.

RESULTS AND LIMITATIONS

The detection rate of GGG ≥2 cancers increased to 30%, 39%, and 49% by adding 4 PL cores, 14, and 24 RB cores, respectively, to TB cores (all p values <0.01). On the whole, TB alone, 14-core RB, and 24-core-RB identified 38%, 47%, and 56% of all the GGG ≥2 cancers. Such figures increased to 62% by adding to TB 4 PL cores, and to 80% by adding 14 RB cores. Most of the differences were observed in PI-RADS 4 lesions.

CONCLUSIONS

We found that PL biopsy increased the detection rate of GGG ≥2 cancers as compared with TB alone. However, the combination of those cores missed a large percentage of the CS cancers identified with larger RB cores, including a 20% of CS cancers diagnosed only by the combination of TB plus 24-core RB.

[Systematic or targeted fusion-guided biopsy]

BACKGROUND

Early detection of prostate cancer (PCa) is associated with a high risk for detecting low-risk disease. In the primary biopsy indication, systematic biopsy leads to an increased detection of clinically insignificant PCa, and significant prostate cancers are not detected with sufficient sensitivity, especially without prior magnetic resonance imaging (MRI). Similar data have recently become available for PCa screening.

OBJECTIVES

In light of the current literature, this article aims to discuss the data on systematic and combined targeted and systematic multiparametric MRI (mpMRI)-guided fusion biopsy to improve PCa diagnosis in clinically suspected cancer even in screening using multivariable risk stratification.

MATERIALS AND METHODS

Literature review on mpMRI and MRI/TRUS fusion biopsy (TRUS: transrectal ultrasonography) for tumor detection in suspected prostate cancer and PCa screening was performed.

RESULTS

Multiparametric MRI as a reflex test after prostate-specific antigen (PSA) determination (PSA cut-off 4 ng/ml) in combination with targeted biopsy alone reduces the detection of clinically nonsignificant tumors in early detection by half. On the other hand, in the form of a target saturation or in combination with a systematic biopsy, the sensitivity for the detection of cancers of International Society of Urogenital Pathology (ISUP) grade groups 2 or higher can be improved. Similar results are also shown in PCa screening with a PSA cut-off of 3 ng/ml.

CONCLUSIONS

The evidence for performing a targeted fusion biopsy alone is currently insufficient. Therefore, the combination of mpMRI-guided targeted and systematic biopsy continues to be the recommended standard for prostate cancer diagnosis.

Assessing the diagnostic performance of systematic freehand PrecisionPoint transperineal prostate biopsy: Comparison of observed outcomes to PBCG nomogram predictions

OBJECTIVE

We assessed the diagnostic performance of freehand systematic transperineal biopsy (fTPb) by using the Prostate Biopsy Collaborative Group (PBCG) nomogram, which is a contemporary update to the PCPT nomogram.

METHODS

From 1/2012 to 12/2018, fTPb was performed on consecutive men with clinical suspicion of prostate cancer. Patients included in this study had no previous diagnosis of prostate cancer, PSA between 2.5 ng/ml and 20 ng/ml, and underwent at least 12 core biopsies. In addition, those men who underwent pre-biopsy multiparametric magnetic resonance imaging of the prostate were considered separately from those without prebiopsy imaging. Biopsies were performed by a single urologist who developed the needle guidance device used in the procedure. Clinical and pathological data were collected retrospectively. We compared observed biopsy outcomes with those predicted by PBCG nomogram utilizing chi-square statistical analysis.

RESULTS

Systematic fTPb (without pre-biopsy MRI) was performed in 301 men (median age 67, mean PSA 6.9 ng/mL). These men had a median of 20 biopsy cores. Clinically significant cancer (ISUP 2 or greater) was found in 33.9% of men. In men without pre-biopsy MRI, using PBCG Nomogram, we found no significant difference between the expected and observed number of clinically significant cancer (96 vs. 102; P = 0.09). An additional 73 men (median age 67, mean PSA 7.8 ng/ml) underwent pre-biopsy MRI imaging. The addition of MRI targets to systematic sampling resulted in a median of 25 cores. Clinically significant cancer was found in 49.3%. Using the PBCG Nomogram, in the men with pre-biopsy MRI we found clinically significant cancer in significantly more men than was expected by PBCG nomogram predictions (36 vs. 20; P = <0.01). There were no biopsy-related infectious complications.

CONCLUSION

The fTPb technique is a promising method to sample the prostate which provides cancer detection that is comparable to that expected from systematic TRUS biopsy. We found that pre-biopsy mpMRI resulted in greater than expected detection of clinically significant cancer when utilizing this technique.

Gleason grade accuracy of transperineal and transrectal prostate biopsies in MRI-naïve patients

PURPOSE

Accurate assessment of Gleason grade is essential to guiding prostate cancer management. Not all healthcare systems have universal access to prostate MRI. We investigated whether transperineal (TP) prostate biopsies provide more accurate Gleason grading than transrectal (TR) biopsies in MRI-naïve patients.

METHODS

Consecutive patients undergoing TP and TR systematic prostate needle biopsies from 2011 to 2018 were analysed. Patients who underwent radical prostatectomy (RP) within 180 days of biopsies were included. Patients undergoing MRI prior to biopsies were excluded. Pathological concordance, incidence of Gleason upgrading, and correlation coefficients among biopsies and RP Gleason grade were compared. A sub-analysis for concordance in anterior prostate tumours was conducted.

RESULTS

262 patients were included (112 TP; 150 TR), the median age was 63 years, and median time from biopsy to RP was 68 days. Concordance with RP histology for TP was 65% compared to 49% for TR (p = 0.011). Biopsy technique predicted RP concordance independent of the number of cores. Gleason upgrading occurred following 24% of TP versus 33% of TR biopsies. In anterior and apical tumours, upgrading occurred in 19% of TP biopsies and 38% of TR biopsies (p = 0.027).

CONCLUSION

This study suggests TP approach to prostate biopsies result in improved histological grade accuracy in men whom MRI is not available, even after controlling for number of cores. TP approach also resulted in less upgrading for lesions in the anterior and apical prostate compared to TR.

Serum miRNAs Support the Indication for MRI-Ultrasound Fusion-Guided Biopsy of the Prostate in Patients with Low-PI-RADS Lesions

Multiparametric MRI (mpMRI) and targeted biopsy of the prostate enhance the tumor detection rate. However, the prediction of clinically significant prostate cancer (PCa) is still limited. Our study tested the additional value of serum levels of selected miRNAs in combination with clinical and mpMRI information for PCa prediction and classification. A total of 289 patients underwent targeted mpMRI-ultrasound fusion-guided prostate biopsy complemented by systematic biopsy. Serum miRNA levels of miRNAs (miR-141, miR-375, miR-21-5p, miR-320b, miR-210-3p, let-7c, and miR-486) were determined by quantitative PCR. Detection of any PCa and of significant PCa were the outcome variables. The patient age, pre-biopsy PSA level, previous biopsy procedure, PI-RADS score, and serum miRNA levels were covariates for regularized binary logistic regression models. The addition of miRNA expression of miR-486 and let-7c to the baseline model, containing only clinical parameters, increased the predictive accuracy. Particularly in patients with PI-RADS ≤3, we determined a sensitivity for detecting significant PCa (Gleason score ≥ 7a corresponding to Grade group ≥2) of 95.2%, and an NPV for absence of significant PCa of 97.1%. This accuracy could be useful to support patient counseling in selected cases.

Transperineal Versus Transrectal Targeted Biopsy With Use of Electromagnetically-tracked MR/US Fusion Guidance Platform for the Detection of Clinically Significant Prostate Cancer

OBJECTIVE

To compare transperineal (TP-TBx) and transrectal (TR-TBx) targeted prostate biopsy in a prospective non randomized single surgeon series of MR/US fusion-guided targeted biopsy performed using an electromagnetic tracking platform (NCT04026763).

MATERIALS AND METHODS

In this single-institution prospective study, 168 patients who underwent transperineal systematic 12-core biopsy and TP-TBx with electromagnetic tracking (UroNav, Invivo, Gainesville, FL) were compared to 211 patients who underwent a similar procedure by a transrectal approach. Univariate and multivariate analyses were used to assess if biopsy technique impacted all cancer detection rates or clinically significant (Gleason score >3+4) cancer detection rates.

RESULTS

Patients who underwent TP-TBx were older (68 vs 65 y, P = .014), with a slightly higher rate of PI-RADSv2.0 score (39% vs 28%, P = .039) and higher lesion volume on mpMRI (0.54 vs 0.41 cc, P = .039). The rates of CS disease detection by TP-TBx and TR-TBx were 59% and 54%, respectively. In a multivariate analysis adjusting for PSA, previous biopsy status, prostate volume, PI-RADS score, lesion volume, and lesion location, there was no statistically significant difference in likelihood to detect any PCa (OR, 0.98; 95% CI, 0.56-1.71; P = .940) or CS PCa (OR, 0.94, 95% CI, 0.58-1.51; P = .791).

CONCLUSION

Transperineal targeted biopsy with electromagnetic-tracking is comparable to the transrectal fusion-guided approach in the detection of any PCa and csPCa cancer.

Prostate cancer and the role of biomarkers

PURPOSE

To review available prostate cancer biomarkers and their performance in a clinical order, from prostate cancer detection, to treatment of localized and advanced disease.

METHODS

We used an electronic literature search of the PubMed database using the key words "prostate biomarkers," "genomic markers," and "prostate cancer screening," as well as specific biomarkers, until March 2019.

RESULTS

Prostate-specific antigen (PSA) lacks sensitivity for prostate cancer detection, and PSA derivatives have slightly improved its specificity, but have not resolved the limitations of PSA screening. Prostate cancer biomarkers have emerged as an ancillary tool to guide the clinical decision-making in different clinical scenarios. Urine-based tests can identify patients who may benefit from a prostate biopsy, and issue-based markers are helpful in guiding the decision regarding a second biopsy, stratifying patient with newly diagnosed prostate cancer to active surveillance or treatment, and identifying patients who may benefit from adjuvant treatment after surgery.

CONCLUSIONS

New biomarkers have improved risk stratification in diagnosing and treating prostate cancer. Many of these markers are still considered experimental, and their efficacy and cost utility have not been determined.

Current techniques of prostate biopsy: an update from past to present

Knowing the demerits of the transrectal ultrasound guided biopsy has led to a shift in the general techniques and technology of the prostate biopsy. In addition, the advances in magnetic resonance imaging (MRI) sensitivity and the evidence from the PROMIS trial about its ability to detect clinically significant tumours encourage urologists and industry to implement MRI-guided targeted biopsy. However, the science is still looking how to improve safety and increase its cancer detection rate (CDR).

Initial outcomes of local anaesthetic freehand transperineal prostate biopsies in the outpatient setting

OBJECTIVES

To evaluate the histopathological outcomes, morbidity and tolerability of freehand transperineal (TP) prostate biopsies using the PrecisionPoint™ access system (Perineologic, Cumberland, MD, USA) under local anaesthetic (LA) in the day surgery and outpatient environments, as systematic and targeted biopsies can be taken with the potential for reduced morbidity, particularly sepsis.

PATIENTS AND METHODS

In all, 176 patients underwent freehand TP prostate biopsies from May 2016 to November 2017. The procedure was carried out either under LA alone or with the addition of sedation. Magnetic resonance imaging (MRI) scans were reported using the Prostate Imaging-Reporting and Data System (PI-RADS), version 2. Tolerability was assessed using a visual analogue scale pain score for each procedural stage. Histopathological outcomes and complications were recorded.

RESULTS

The mean (range) age was 65 (36-83) years, median (range) prostate-specific antigen level was 7.9 (0.7-1374) ng/mL, and the mean (range) prostate volume 45 (15-157) mL. Biopsies were taken under LA alone (160 patients, 90%) or under LA with sedation (16, 9%). The main indication for biopsy was primary diagnosis (88.6%). In all, 91 (52%) patients underwent systematic TP biopsies (mean 24.2 cores). Cognitive MRI-targeted biopsies alone were performed in 45 patients (26%; mean 6.8 cores), and 40 (23%) had both systematic and target biopsies (mean 27.9 cores). Of the 75 patients who had primary systematic biopsies alone, 46 (61%) were positive, and 28/46 (60.9%) were diagnosed with clinically significant disease (Gleason ≥3+4). VAS pain scores were greatest during LA administration. There were five complications (2.8%, Clavien-Dindo Grade I/II). No patients developed urosepsis.

CONCLUSIONS

Freehand TP biopsies using the PrecisionPoint access system is a safe, tolerable and effective method for systematic and targeted biopsies under LA in the outpatient setting. It has replaced transrectal biopsies in our centre and has potential to transform practice.

[Importance of magnetic resonance imaging/ultrasound-guided fusion biopsy for the detection and monitoring of prostate cancer]

The use of multiparametric magnetic resonance imaging (mpMRI) is becoming increasingly more important for the primary diagnostics of prostate cancer (PCa) and for monitoring under active surveillance. Current studies confirmed that the use of mpMRI can increase the detection of clinically significant PCa and reduce the detection rate of insignificant PCa as well as the rate of unnecessary biopsies. The information from mpMRI can be cognitively used for in-bore biopsy and using fusion biopsy systems. There are no clear recommendations on the access approach for fusion biopsy (e. g. transrectal or perineal), whereby higher rates of rectal bleeding and infections have been described for transrectal access compared to perineal access. The increasing rate of antibiotic resistance as well as restricted indications for the use of quinolones are a major challenge for transrectal biopsy.

The Specific Choice of Transrectal Ultrasound-Guided Prostate Biopsy Scheme Based on Prostate Specific Antigen and Prostate Specific Antigen Density

Background

Although magnetic resonance imaging (MRI)-targeted biopsy and saturation biopsy can improve the accuracy of prostate biopsy, transrectal ultrasound (TRUS)-guided prostate biopsy is still the cornerstone for diagnosis of prostate cancer. However, it is not clear whether it is necessary to perform the same TRUS-guided biopsy scheme for patients with different prostate specific antigen (PSA) or prostate specific antigen density (PSAD) levels. The purpose of this study was to evaluate the optimal core number for specific suspected prostate cancer patients.

Material/Methods

There were 398 patients who underwent 12-core biopsy scheme, who were included in this retrospective analysis. The 12-core scheme incorporated a classic sextant scheme and 4-core biopsies from the base and middle regions bilaterally. The cancer detection rates of patients with different PSA or PSAD levels between the 12-core, sextant, 4-core, and 2-core biopsy were compared.

Results

The differences in cancer detection rates between the 12-core biopsy scheme and the sextant biopsy scheme were significant in patients with PSA <20 ng/mL or PSAD <0.3. There were no differences in the cancer detection rates between the 12-core biopsy scheme and the 4-core biopsy scheme in patients with PSA ≤50 ng/mL or PSAD ≤1.0. There were significant differences between 12-core and 2-core scheme when PSA ≤70 ng/mL or PSAD ≤1.5.

Conclusions

We recommend that the 12-core biopsy should be used for patients with PSA <20 ng/mL or PSAD <0.3. The biopsy scheme in patients with PSA 20–50 ng/mL or PSAD 0.3–1.0 should be considered in combination with DRE and MRI. For patients with PSA >50 ng/mL or PSAD >1.0, we recommend 6-core or 4-core biopsy by comprehensively considering multiple factors. The 2-core biopsy is recommended for patients with PSA >70 ng/mL or PSAD >1.5.

Magnetic resonance imaging-guided targeted biopsy in risk classification among patients on active surveillance: A diagnostic meta-analysis

BACKGROUND

The aim of this study was to assess the sensitivity and accuracy of magnetic resonance imaging-guided targeted biopsy (MRI-TB) in patients undergoing active surveillance (AS) procedure.

METHODS

We searched databases to identify relevant studies which compared MRI-TB with systemic biopsy for diagnosing prostate cancer in patients on AS. Outcomes included sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), area under the curve (AUC) and publication bias of AS group, confirmatory biopsy group and follow-up biopsy group.

RESULTS

Fourteen articles involving 1693 patients were included. In AS group, the sensitivity was 0.62 (95% confidence interval [CI], 0.57-0.68), specificity was 0.89 (95% CI, 0.87-0.90), NLR was 0.43 (0.31-0.60), PLR was 4.90 (3.50-6.86), DOR was 12.75 (7.22-22.51), and AUC was 0.8645. In confirmatory biopsy group, the sensitivity was 0.67 (0.59-0.74), specificity was 0.89 (0.86-0.91), NLR was 0.42 (0.27-0.65), PLR was 4.94 (3.88-6.30), DOR was 14.54 (9.60-22.02), and AUC was 0.8812. In follow-up biopsy group, the sensitivity was 0.35 (0.22-0.51), specificity was 0.88 (0.82-0.92), NLR was 0.76 (0.52-1.11), PLR was 3.06 (1.71-5.50), DOR was 4.41 (2.15-9.03), and AUC was 0.8367.

CONCLUSION

MRI-TB has a moderate-to-high diagnostic accuracy for diagnosing and reclassifying patients on AS with high specificity and AUC value under the SROC curve.

Controversies in MR targeted biopsy: alone or combined, cognitive versus software-based fusion, transrectal versus transperineal approach?

PURPOSE

To review the evidence addressing current controversies around prostate biopsy. Specific questions explored were (1) mpMRI targeted (TgBx) alone versus combined with systematic (SBx) biopsy; (2) cognitive versus software-based targeted biopsy; (3) transrectal or transperineal route (TP).

METHODS

We performed a literature search of peer-reviewed English language articles using PubMed and the words "prostate" AND "biopsy". Web search was implemented by manual search.

RESULTS

Prostate mpMRI is revolutionizing prostate cancer (PCa) diagnosis, and TgBx improves the detection of clinically significant (cs) PCa compared to SBx alone. The utility of combining SBx-TgBx is variable, but in non-expert centres the two should be combined to overcome learning curve-limitations. Whether SBx should be maintained in expert centres depends on what rate of missed cancer the urological community and patients are prone to accept; this has implications for insignificant cancer diagnosis as well. TgBx may be more precise using a software-based-approach despite cognitive TgBx proved non-inferior in some studies, and may be used for large accessible lesions. TP-biopsies are feasible in an in-office setting. Avoidance of the rectum and accessibility of virtually all prostate areas are attractive features. However, this has to be balanced with local setting and resources implications. Ongoing trials will shed light on unsolved issues.

CONCLUSION

The prostate biopsy strategy should be tailored to local expertise, needs and resources availability. Targeted biopsy enhance the ratio between cs and insignificant cancer diagnosis, although some csPCa might be missed. Software-based TgBx are likely to be more precise, especially for new users, although the additional cost might be not justified in all cases. TPBx have ideal attributes for performing TgBx and avoiding infection, although this has resources implications.

Anatomic and Molecular Imaging in Prostate Cancer

Prostate cancer is characterized by a complex set of heterogeneous disease states. This review aims to describe how imaging has been studied within each specific state. As physicians transition into an era of precision medicine, multiparametric magnetic resonance imaging (mpMRI) is proving to be a powerful tool leading the way for a paradigm shift in the diagnosis and management of localized prostate cancer. With further research and development, molecular imaging modalities will likely change the way we approach recurrent and metastatic disease. Given the range of possible oncological progression patterns, a thorough understanding of the underlying carcinogenesis, as it relates to imaging, is a requisite if we are to appropriately manage prostate cancer in future decades.

Transrectal ultrasound-guided prostate rebiopsy: How many core sampling should be applied to which patient?

Background:

We investigated the correlation between the sampled number of cores in rebiopsy and the cancer detection rate (CDR).

Materials and Methods:

Two hundred and twelve patients with normal rectal examination who had undergone rebiopsy in the past 5 years were examined retrospectively. Moreover, 68% of them had undergone 12 cores (Group 1) while 32% had undergone 20 cores (Group 2). Both groups were compared with respect to the CDR.

Results:

There was no difference between groups in terms of age, total prostate-specific antigen, and prostate volume (P > 0.05). Forty-one (19%) of 212 patients were diagnosed with cancer, and the CDR was significantly higher in Group 2 (30.9% vs. 13.9%, P = 0.004). This rate increased from 6.5% to 20% (P = 0.025) and from 0% to 33.3% (P = 0.023), respectively, with 12-core and 20-core rebiopsies in patients whose initial pathology indicated benign and high-grade prostatic intraepithelial neoplasia (HGPIN). Furthermore, cancer was detected in 24 (40%) of 60 patients who were diagnosed with atypical small acinar proliferation (ASAP) in the initial biopsy. However, despite being higher in 20-core biopsy group (47.6% vs. 35.9%), this was not statistically significant (P = 0.377).

Conclusions:

At least 20 cores should be sampled in rebiopsy, especially in the patients diagnosed with benign and HGPIN. However, we believe that standard systematic sampling will be sufficient for the patients diagnosed with ASAP.

Candidate diagnostic miRNAs that can detect cancer in prostate biopsy

BACKGROUND

While histopathological evaluation remains the gold standard for diagnosis of prostate cancer (PCa), sampling errors remain a frequent problem; therefore, use of tissue biomarkers that can distinguish between benign and malignant prostate disease is a potentially beneficial diagnostic strategy.

METHODS

Deep sequencing of the miRNA transcriptome of 14 benign prostatic hyperplasia (BPH) and 60 cancerous and non-cancerous prostate samples extracted from 34 cancer-bearing prostates removed by prostatectomy was performed; of the latter 60 samples, 16, 21, and 23 samples contained <10%, >30%, and no dysplastic cells, respectively. The predictive value of selected miRNAs was then tested by quantitative reverse-transcribed PCR (qRT-PCR), using two separate chemistries, Exiqon and Taqman, to evaluate the tissue samples obtained by prostatectomy. Validation experiments were also performed for a subset of miRNAs by qRT-PCR of 87 prostate core biopsies.

RESULTS

We identified 123 miRNAs significantly dysregulated in PCa (adjusted P-values <0.05); 110 and 13 miRNAs were dysregulated only in cancerous samples and non-cancerous samples extracted from cancer-bearing prostates, respectively, while 31 were dysregulated regardless of the dysplastic cell content of the studied specimens. The clinical utility of eight selected miRNAs was analyzed using the same sample set with two qRT-PCR chemistries. Measurable qRT-PCR signals were obtained for seven and six miRNAs using the Exiqon and Taqman chemistries, respectively, and expression levels of six and four of these miRNAs differed significantly between BPH and PCa samples, regardless of dysplastic cell content. Validation experiments on core biopsies using qRT-PCR confirmed differential expression between BPH and PCa of four miRNAs (miR-187-3p, miR-183-5p, miR-32-5p, and miR-141-5p) using the Exiqon and one miRNA (miR-187-3p) with the Taqman chemistry.

CONCLUSIONS

Our sequencing analyses identified several candidate diagnostic miRNAs and confirmed some which have previously been reported as diagnostic in prostate malignancy. The results of this study suggest also that some of selected miRNAs can differentiate between non-malignant and malignant prostates even when neoplastic cells are missing from the studied specimen.

Risk of Upgrading from Prostate Biopsy to Radical Prostatectomy Pathology-Does Saturation Biopsy of Index Lesion during Multiparametric Magnetic Resonance Imaging-Transrectal Ultrasound Fusion Biopsy Help?

PURPOSE

We sought to determine whether saturation of the index lesion during magnetic resonance imaging-transrectal ultrasound fusion guided biopsy would decrease the rate of pathological upgrading from biopsy to radical prostatectomy.

MATERIALS AND METHODS

We analyzed a prospectively maintained, single institution database for patients who underwent fusion and systematic biopsy followed by radical prostatectomy in 2010 to 2016. Index lesion was defined as the lesion with largest diameter on T2-weighted magnetic resonance imaging. In patients with a saturated index lesion transrectal fusion biopsy targets were obtained at 6 mm intervals along the long axis of the index lesion. In patients with a nonsaturated index lesion only 1 target was obtained from the lesion. Gleason 6, 7 and 8-10 were defined as low, intermediate and high risk, respectively.

RESULTS

Included in the study were 208 consecutive patients, including 86 with a saturated and 122 with a nonsaturated lesion. Median patient age was 62.0 years (IQR 10.0) and median prostate specific antigen was 7.1 ng/ml (IQR 8.0). The median number of biopsy cores per index lesion was higher in the saturated lesion group (4 vs 2, p <0.001). The risk category upgrade rate from systematic only, fusion only, and combined fusion and systematic biopsy results to prostatectomy was 40.9%, 23.6% and 13.8%, respectively. The risk category upgrade from combined fusion and systematic biopsy results was lower in the saturated than in the nonsaturated lesion group (7% vs 18%, p = 0.021). There was no difference in the upgrade rate based on systematic biopsy between the 2 groups. However, fusion biopsy results were significantly less upgraded in the saturated lesion group (Gleason upgrade 20.9% vs 36.9%, p = 0.014 and risk category upgrade 14% vs 30.3%, p = 0.006).

CONCLUSIONS

Our results demonstrate that saturation of the index lesion significantly decreases the risk of upgrading on radical prostatectomy by minimizing the impact of tumor heterogeneity.

Does magnetic resonance imaging-guided biopsy improve prostate cancer detection? A comparison of systematic, cognitive fusion and ultrasound fusion prostate biopsy

Background

The increase in the use of multiparametric magnetic resonance imaging for the detection of prostate cancer has led to the rapid adoption of MRI-guided biopsies (MRGBs). To date, there is limited evidence in the use of MRGB and no direct comparisons between the different types of MRGB. We aimed to assess whether multiparametric MRGBs with MRI-US transperineal fusion biopsy (FB) and cognitive biopsy (CB) improved the management of prostate cancer and to assess if there is any difference in prostate cancer detection with FB compared with CB.

Methods

Patients who underwent an MRGB and a systematic biopsy (SB) from June 2014 to August 2016 on the Central Coast, NSW, Australia, were included in the study. The results of SB were compared with MRGB. The primary outcome was prostate cancer detection and if MRGB changed patient management.

Results

A total of 121 cases were included with a mean age of 65.5 years and prostate-specific antigen 7.4 ng/mL. Seventy-five cases (62%) had a Prostate Imaging and Reporting Data System 4–5 lesions and 46 (38%) had a Prostate Imaging and Reporting Data System 3 lesions. Fifty-six cases underwent CB and 65 underwent FB.

Of the 93 patients with prostate cancer detected, 19 men (20.5%) had their management changed because of the MRGB results. Eight men (9%) had prostate cancer detected on MRGB only and 12 men (13%) underwent radical prostatectomy or radiotherapy based on the MRGB results alone.

There was a trend to a higher rate of change in management with FB compared with CB (29% vs. 18%).

Conclusions

This is one of the first Australian studies to assess the utility of MRGB and compare FB with CB. MRGB is a useful adjunct to SB, changing management in over 20% of our cases, with a trend toward FB having a greater impact on patient management compared with CB.

Validation of Prostate Imaging-Reporting and Data System Version 2: A Retrospective Analysis

PURPOSE

Use of magnetic resonance imaging (MRI)/transrectal ultrasound fusion biopsies to determine the accuracy of multiparametric MRI (mpMRI), using Prostate Imaging-Reporting and Data System version 2 (PI-RADSv2), for detecting clinically significant prostate cancer in the overall gland and specifically the peripheral zone (PZ) and transitional zone (TZ).

METHODS

A retrospective analysis of patients who underwent fusion biopsy identified 137 men with 231 prostate lesions was approved by the Institutional Review Board. Subjects initially classified under PI-RADSv1 criteria were regraded using PI-RADSv2 by a radiologist blinded to PI-RADSv1 score and biopsy results. Spearman correlation, chi-squared, and logistic regression analysis were performed.

RESULTS

There was positive correlation between PI-RADSv2 and Gleason scores (P < 0.001). In the PZ, mpMRI demonstrated 100% sensitivity, 100% negative predictive value, and 35.9% positive predictive value, compared to 100%, 100%, and 27.1%, respectively, for TZ lesions. When predicting clinically significant prostate cancer, the PI-RADSv2 area under the curve for TZ lesions was 0.844 (95% CI: 0.753-0.935, P < 0.001) and 0.769 (95% CI: 0.684-0.854, P < 0.001) for PZ lesions. Combining PI-RADSv2 with additional risk factors (body mass index, prostate-specific antigen density, digital rectal examination) improved the area under curve.

CONCLUSIONS

PI-RADSv2 achieves excellent sensitivity and negative predictive value for both PZ and TZ lesions.

[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.

Transrectal real-time tissue elastography targeted biopsy coupled with peak strain index improves the detection of clinically important prostate cancer

The focus of the present study was to evaluate transrectal real-time tissue elastography (RTE)-targeted two-core biopsy coupled with peak strain index for the detection of prostate cancer (PCa) and to compare this method with 10-core systematic biopsy. A total of 141 patients were enrolled for evaluation. The diagnostic value of peak strain index was assessed using a receiver operating characteristic curve. The cancer detection rates of the two approaches and corresponding positive cores and Gleason score were compared. The cancer detection rate per core in the RTE-targeted biopsy (44%) was higher compared with that in systematic biopsy (30%). The peak strain index value of PCa was higher compared with that of the benign lesion. PCa was detected with the highest sensitivity (87.5%) and specificity (85.5%) using the threshold value of a peak strain index of ≥5.97 with an area under the curve value of 0.95. When the Gleason score was ≥7, RTE-targeted biopsy coupled with peak strain index detected 95.6% of PCa cases, but 84.4% were detected using systematic biopsy. Peak strain index as a quantitative parameter may improve the differentiation of PCa from benign lesions in the prostate peripheral zone. Transrectal RTE-targeted biopsy coupled with peak strain index may enhance the detection of clinically significant PCa, particularly when combined with systematic biopsy.

[Prostate gland - what would urologists like to know from radiologists?]

A more than 100-year period, where the prostate was only seen and treated as a whole is coming to an end right now. Finally, high resolution imaging is providing deep insights and detailed information so that new therapeutic procedures can aim for the smallest targets within the gland. The long-standing wish of patients for individual noninvasive diagnostics and treatment of prostate diseases can now be fulfilled by providing new tailored concepts; however, in order to transfer the enormous amount of new information into the specific clinical patient situation, a closely knit interdisciplinary approach is required. In this setting, the traditional outpatient consultation service is overstretched in every aspect. It is now the time for new innovative constructs. The current one-sided service concept for urologists, radiologists and radiation therapists is therefore behind the times and the development of a "prostate management team" with equally cooperating partners from each specialty is the task for the future.

Prospective Evaluation of PI-RADS™ Version 2 Using the International Society of Urological Pathology Prostate Cancer Grade Group System

PURPOSE

The PI-RADS™ (Prostate Imaging Reporting and Data System), version 2 scoring system, introduced in 2015, is based on expert consensus. In the same time frame ISUP (International Society of Urological Pathology) introduced a new pathological scoring system for prostate cancer. Our goal was to prospectively evaluate the cancer detection rates for each PI-RADS, version 2 category and compare them to ISUP group scores in patients undergoing systematic biopsy and magnetic resonance imaging-transrectal ultrasound fusion guided biopsy.

MATERIALS AND METHODS

A total of 339 treatment naïve patients prospectively underwent multiparametric magnetic resonance imaging evaluated with PI-RADS, version 2 with subsequent systematic and fusion guided biopsy from May 2015 to May 2016. ISUP scores were applied to pathological specimens. An ISUP score of 2 or greater (ie Gleason 3 + 4 or greater) was defined as clinically significant prostate cancer. Cancer detection rates were determined for each PI-RADS, version 2 category as well as for the T2 weighted PI-RADS, version 2 categories in the peripheral zone.

RESULTS

The cancer detection rate for PI-RADS, version 2 categories 1, 2, 3, 4 and 5 was 25%, 20.2%, 24.8%, 39.1% and 86.9% for all prostate cancer, and 0%, 9.6%, 12%, 22.1% and 72.4% for clinically significant prostate cancer, respectively. On T2-weighted magnetic resonance imaging the cancer detection rate in the peripheral zone was significantly higher for PI-RADS, version 2 category 4 than for overall PI-RADS, version 2 category 4 in the peripheral zone (all prostate cancer 36.6% vs 48.1%, p = 0.001, and clinically significant prostate cancer 22.9% vs 32.6%, p = 0.002).

CONCLUSIONS

The cancer detection rate increases with higher PI-RADS, version 2 categories.

Predictors of prostate cancer in ultrasound-guided transperineal saturation biopsy in Turkish men with multiple prior negative biopsies

BACKGROUND

Transperineal prostate biopsy (STPB) is associated with an improved cancer detection rate and an increase in anterior and apical prostate cancers compared to standard transrectal biopsy.

PATIENTS AND METHODS

A total of 48 men with at least two sets of prior prostate biopsies underwent transrectal ultrasound-guided STPB. Prostate rebiopsy indications were serum prostate-specific antigen (PSA) levels greater than 2.5 ng/mL and/or abnormal digital rectal examination and/or presence of high-grade prostatic intraepithelial neoplasia (HGPIN; ≥2 cores) or atypical small acinar proliferation (ASAP) at previous biopsies. The procedure was performed at dorsal lithotomy position under general anesthesia using a perineal 0.5 cm brachytherapy template attached to the transrectal ultrasound probe. Specimens from each zone were sent separately for pathological examination.

RESULTS

Mean PSA level at STPB was 15.9 ng/mL (range 4.03 to 59.57). An average of 54.5 cores was obtained. Prostate adenocarcinoma was detected in 15 of 48 (31%) patients. Mean percentage of malignant cores was 11.9%. Multivariate logistic regression analysis revealed that age and presence of ASAP or HGPIN at previous biopsies were independent predictors of prostate cancer (p&lt;0.05). No major complications, including sepsis and severe urinary or rectal bleeding, were observed in any of the patients. Five patients (10%) developed acute urinary retention after the procedure requiring urethral catheterization.

CONCLUSIONS

Considerable number of patients with negative multiple biopsies were diagnosed with prostate cancer. STPB is a well-tolerated procedure with minimal morbidity, which can be considered for the diagnosis of prostate cancer in patients with previous negative biopsies.

Assessing Cancer Risk on Novel 29 MHz Micro-Ultrasound Images of the Prostate: Creation of the Micro-Ultrasound Protocol for Prostate Risk Identification

PURPOSE

Conventional ultrasound systems operate at 6 to 9 MHz and serve as the standard of care to guide prostate biopsies. We present a protocol using a novel high resolution (29 MHz) transrectal prostate micro-ultrasound system. This protocol includes a scoring system to assess the risk of prostatic carcinoma and enable real-time targeted biopsies.

MATERIALS AND METHODS

The ExactVu™ system is currently being used in a multisite, 2,000-patient, randomized clinical trial. Cine loops of 400 biopsies from this trial were used to create the PRI-MUS™ (prostate risk identification using micro-ultrasound) protocol and risk scale. Validation was performed in an independent, pathology blinded set of 100 cines. Three of the 5 investigators performing this validation were familiar with micro-ultrasound but naïve to the PRI-MUS protocol and they received only 1 hour of training.

RESULTS

Each increase in risk score demonstrated a 10.1% increase (95% CI 9.3-10.8) in the probability of clinically significant cancer. The risk score also increased with Gleason sum and cancer length with a slope of 0.15 (95% CI 0.09-0.21) and 0.58 (95% CI 0.43-0.73), respectively. Sensitivity and specificity were 80% and 37%, respectively, and the mean ± SD ROC AUC was 60% ± 2%. The protocol was more accurate for detecting high grade disease (Gleason sum greater than 7) with a peak AUC of 74% (mean 66%).

CONCLUSIONS

The new resolution of the micro-ultrasound platform paired with the PRI-MUS protocol shows promise for real-time visualization of suspicious lesions and targeting of biopsies. The improved performance of the protocol in more significant disease is consistent with the focus of the field on decreasing insignificant diagnoses and detecting high risk disease early.

Probability modeling of the number of positive cores in a prostate cancer biopsy session, with applications

Among men, prostate cancer (CaP) is the most common newly diagnosed cancer and the second leading cause of death from cancer. A major issue of very large scale is avoiding both over-treatment and under-treatment of CaP cases. The central challenge is deciding clinical significance or insignificance when the CaP biopsy results are positive but only marginally so. A related concern is deciding how to increase the number of biopsy cores for larger prostates. As a foundation for improved choice of number of cores and improved interpretation of biopsy results, we develop a probability model for the number of positive cores found in a biopsy, given the total number of cores, the volumes of the tumor nodules, and - very importantly - the prostate volume. Also, three applications are carried out: guidelines for the number of cores as a function of prostate volume, decision rules for insignificant versus significant CaP using number of positive cores, and, using prior distributions on total tumor size, Bayesian posterior probabilities for insignificant CaP and posterior median CaP. The model-based results have generality of application, take prostate volume into account, and provide attractive tradeoffs of specificity versus sensitivity. Copyright © 2015 John Wiley & Sons, Ltd.

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.

Diagnostic Performance of Initial Transperineal Template-guided Mapping Biopsy of the Prostate Gland

OBJECTIVES

To evaluate the utility of transperineal template-guided mapping biopsy (TTMB) of the prostate as an initial means of establishing tissue diagnosis.

MATERIALS AND METHODS

A total of 191 consecutive patients underwent TTMB of the prostate using an anatomic-based technique with sampling of 24 regions. All patients had elevated prostate-specific antigen on routine screening which was followed by a confirmatory prostate-specific antigen and none had undergone previous biopsy of the prostate. The locations of cancer involvement were recorded for each patient in an effort to approximate the percentage of men whose cancer would have been missed or Gleason score underestimated on a standard 12-core biopsy. The median number of submitted biopsy cores was 54.0.

RESULTS

Of the 191 study patients, 140 (73.3%) were diagnosed with cancer on TTMB. Among these biopsy-positive patients, 124 (88.6%) had clinically significant cancer. Eighty-nine of the biopsy-positive patients (64.6%) had a Gleason score of ≥7. A total of 34 of the 140 diagnosed cancers were identified exclusively in regions that fell outside of the theoretical 12-core biopsy scheme, suggesting that 24.3% of these cancers would have gone undiagnosed in the absence of TTMB. Among the 107 cancers that would have been diagnosed using a 12-core biopsy approach, 18 (16.8%) were upgraded to a Gleason score of ≥7 with mapping biopsy.

CONCLUSIONS

TTMB appears to provide more detailed information about prostate cancer grade and location compared with standard 12-core biopsy scheme. This information may serve as a baseline reference for image-guided biopsy (ie, magnetic resonance imaging) regimens, may facilitate clinical decision making and aid in the appropriate selection of patients for active surveillance.

Fluoroquinolone-based antimicrobial prophylaxis in patients undergoing transrectal ultrasound-guided prostate biopsy

The aim of this study was to establish the prevalence of resistance to fluoroquinolones in Escherichia coli strains isolated from patients undergoing transrectal ultrasound-guided prostate biopsy (TRUS-Bx) and to evaluate the incidence of possible infectious complications associated with this procedure. One hundred and four patients undergoing a TRUS-Bx in a single medical centre were prospectively enrolled in this study. In all patients, pre-biopsy rectal swabs were obtained. The analysis determined the antimicrobial susceptibility of E. coli strains to levofloxacin, ciprofloxacin and a panel of other antibiotics. Before biopsy, each of the men received a levofloxacin-based prophylaxis. Telephone follow-up was used to identify patients who had complications after TRUS-Bx. Fluoroquinolone-resistant strains were isolated from 9.62 % of the patients. In all cases, there were related to E. coli and all those strains were resistant to both levofloxacin and ciprofloxacin. Fluoroquinolones showed greater antimicrobial activity against E. coli (p < 0.05) than ampicillin, amoxicillin/clavulanate and cephalothin. Minor infectious complications occurred in three patients (2.91 %). The relation between the resistance of E. coli to fluoroquinolones and the risk of readmission, as well as infectious complications, was statistically significant (p < 0.05). Despite recent reports of increasing prevalence of fluoroquinolone-resistant E. coli and the associated increase of severe infectious complications, the presented results have not confirmed this phenomenon. Resistance to fluoroquinolones of E. coli strains isolated from rectal swab cultures prior to TRUS-Bx is the risk factor for readmission and infectious complications after this procedure.

Prostate Biopsy Using Transrectal Ultrasonography; The Optimal Number of Cores Regarding Cancer Detection Rate and Complications

BACKGROUND

Transrectal ultrasound guided biopsy of the prostate is the most common modality used to diagnose prostate cancer.

OBJECTIVES

The aim of this study was to evaluate the optimal number of cores at prostate biopsy, which have the most diagnostic value with least adverse effects.

PATIENTS AND MATERIALS

Transrectal ultrasonography (TRUS) guided biopsy was performed in 180 patients suspicious for prostate cancer due to either abnormal rectal examination or elevated PSA. The patients were divided randomly into three groups of six-core, twelve-core and eighteen-core biopsies. The detection rate of prostate cancer in each group with the rate of post biopsy urinary infection and prostatitis were compared.

RESULTS

Prostate cancer was diagnosed in 8 (13.3%), 21 (35%) and 24 (40%) patients in six, twelve and eighteen core biopsy groups, respectively. Urinary tract infection and prostatitis occurred in 17 (28.3%), 23 (38.3%) and 35 (58.3%) patients in six, twelve and eighteen core biopsy groups, respectively. Considering the detection rate of prostate cancer, there was a significant difference between 6 and 12 core biopsy groups (P = 0.006) and 12-core biopsies detected more cases of prostate cancer, but there was no significant difference between 12 and 18 core biopsy groups (P = 0.572). Considering the infection rate, there was no significant difference between 6 and 12 core biopsy groups (P = 0.254), but there was a significant difference between 12 and 18 core biopsy groups (P = 0.028) and infectious complications occurred more frequently in 18-core biopsy group.

CONCLUSIONS

The best balance between detection rate of prostate cancer and infectious complications of biopsies achieved in twelve-core biopsy protocol. Twelve-core biopsy enhances the rate of prostate cancer detection with minimum adverse effects.

The role of transrectal ultrasound in the diagnosis of prostate cancer: new contributions

Objective

The present study was aimed at evaluating the contribution of transrectal prostate ultrasound in the screening for prostate neoplasias and in the guidance of prostate biopsies.

Materials and Methods

Prospective study developed over a one-year period. All the patients with indication for prostate biopsy were evaluated. Regardless of PSA values, the patients underwent ultrasound in order to identify suspicious nodules (confirmed by two observers). Sextant biopsy was subsequently performed. In cases of finding suspicious nodules, an additional puncture directed to such nodules was done.

Results

In a total of 155 cases the prevalence of malignancy was of 53%. Suspicious nodules were detected in 34 patients, and 25 where malignant (positive predictive value of 74%). The specificity and sensitivity for suspicious nodules were 88% and 31% respectively. Comparatively with the randomly obtained sextant specimens, the rate of findings of neoplasia was higher in the specimens obtained with puncture directed to the nodule (p = 0.032). No statistically significant difference was observed in the Gleason score for both types of specimens (p = 0.172).

Conclusion

The high positive predictive value and the high rate of findings of neoplasia in specimens of suspicious nodules should be taken into consideration in the future. The authors suggest a biopsy technique similar to the one described in the present study (sextant biopsy plus puncture directed to the suspicious nodule).

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.

3-Tesla magnetic resonance imaging improves the prostate cancer detection rate in transrectral ultrasound-guided biopsy

The detection rate of prostate cancer (PCa) using traditional biopsy guided by transrectal ultrasound (TRUS) is not satisfactory. The aim of this study was to determine the utility of 3-Tesla (3-T) magnetic resonance imaging (MRI) prior to TRUS-guided prostate biopsy and to investigate which subgroup of patients had the most evident improvement in PCa detection rate. A total of 420 patients underwent 3-T MRI examination prior to the first prostate biopsy and the positions of suspicious areas were recorded respectively. TRUS-guided biopsy regimes included systematic 12-core biopsy and targeted biopsy identified by MRI. Patients were divided into subgroups according to their serum prostate-specific antigen (PSA) levels, PSA density (PSAD), prostate volume, TRUS findings and digital rectal examination (DRE) findings. The ability of MRI to improve the cancer detection rate was evaluated. The biopsy positive rate of PCa was 41.2% (173/420), and 41 of the 173 (23.7%) patients were detected only by targeted biopsy in the MRI-suspicious area. Compared with the systematic biopsy, the positive rate was significantly improved by the additional targeted biopsy (P=0.0033). The highest improvement of detection rate was observed in patients with a PSA level of 4–10 ng/ml, PSAD of 0.12–0.20 ng/ml², prostate volume >50 ml, negative TRUS findings and negative DRE findings (P<0.05). Therefore, it is considered that 3-T MRI examination could improve the PCa detection rate on first biopsy, particularly in patients with a PSA level of 4–10 ng/ml, PSAD of 0.12–0.20 ng/ml², prostate volume of >50 ml, negative TRUS findings and negative DRE findings.

What is the ideal core number for ultrasound-guided prostate biopsy?

Purpose

We evaluated the utility of 10-, 12-, and 16-core prostate biopsies for detecting prostate cancer (PCa) and correlated the results with prostate-specific antigen (PSA) levels, prostate volumes, Gleason scores, and detection rates of high-grade prostatic intraepithelial neoplasia (HGPIN) and atypical small acinar proliferation (ASAP).

Materials and Methods

A prospective controlled study was conducted in 354 consecutive patients with various indications for prostate biopsy. Sixteen-core biopsy specimens were obtained from 351 patients. The first 10-core biopsy specimens were obtained bilaterally from the base, middle third, apex, medial, and latero-lateral regions. Afterward, six additional punctures were performed bilaterally in the areas more lateral to the base, middle third, and apex regions, yielding a total of 16-core biopsy specimens. The detection rate of carcinoma in the initial 10-core specimens was compared with that in the 12- and 16-core specimens.

Results

No significant differences in the cancer detection rate were found between the three biopsy protocols. PCa was found in 102 patients (29.06%) using the 10-core protocol, in 99 patients (28.21%) using the 12-core protocol, and in 107 patients (30.48%) using the 16-core protocol (p=0.798). The 10-, 12-, and 16-core protocols were compared with stratified PSA levels, stratified prostate volumes, Gleason scores, and detection rates of HGPIN and ASAP; no significant differences were found.

Conclusions

Cancer positivity with the 10-core protocol was not significantly different from that with the 12- and 16-core protocols, which indicates that the 10-core protocol is acceptable for performing a first biopsy.

Standards for prostate biopsy

PURPOSE OF REVIEW

A variety of techniques have emerged for the optimization of prostate biopsy. In this review, we summarize and critically discuss the most recent developments regarding the optimal systematic biopsy and sampling labeling along with multiparametric MRI and magnetic resonance-targeted biopsies.

RECENT FINDINGS

The use of 10-12-core-extended sampling protocols increases cancer detection rates compared with traditional sextant sampling and reduces the likelihood that patients will require a repeat biopsy, ultimately allowing more accurate risk stratification without increasing the likelihood of detecting insignificant cancers. As the number of cores increases above 12 cores, the increase in diagnostic yield becomes marginal. However, the limitations of this technique include undersampling, oversampling, and the need for repetitive biopsy. MRI and magnetic resonance-targeted biopsies have demonstrated superiority over systematic biopsies for the detection of clinically significant disease and representation of disease burden, while deploying fewer cores and may have applications in men undergoing initial or repeat biopsy and those with low-risk cancer on or considering active surveillance.

SUMMARY

A 12-core systematic biopsy that incorporates apical and far-lateral cores in the template distribution allows maximal cancer detection, avoidance of a repeat biopsy while minimizing the detection of insignificant prostate cancers. MRI-guided prostate biopsy has an evolving role in both initial and repeat prostate biopsy strategies, as well as active surveillance, potentially improving sampling efficiency, increasing the detection of clinically significant cancers, and reducing the detection of insignificant cancers.

DNA methylation status is more reliable than gene expression at detecting cancer in prostate biopsy

Background:

We analysed critically the potential usefulness of RNA- and DNA-based biomarkers in supporting conventional histological diagnostic tests for prostate carcinoma (PCa) detection.

Methods:

Microarray profiling of gene expression and DNA methylation was performed on 16 benign prostatic hyperplasia (BPH) and 32 cancerous and non-cancerous prostate samples extracted by radical prostatectomy. The predictive value of the selected biomarkers was validated by qPCR-based methods using tissue samples extracted from the 58 prostates and, separately, using 227 prostate core biopsies.

Results:

HOXC6, AMACR and PCA3 expression showed the best discrimination between PCa and BPH. All three genes were previously reported as the most promising mRNA-based markers for distinguishing cancerous lesions from benign prostate lesions; however, none were sufficiently sensitive and specific to meet the criteria for a PCa diagnostic biomarker. By contrast, DNA methylation levels of the APC, TACC2, RARB, DGKZ and HES5 promoter regions achieved high discriminating sensitivity and specificity, with area under the curve (AUCs) reaching 0.95−1.0. Only a small overlap was detected between the DNA methylation levels of PCa-positive and PCa-negative needle biopsies, with AUCs ranging between 0.854 and 0.899.

Conclusions:

DNA methylation-based biomarkers reflect the prostate malignancy and might be useful in supporting clinical decisions for suspected PCa following an initial negative prostate biopsy.

Random biopsy: when, how many and where to take the cores?

PURPOSE

The optimal random prostate biopsy scheme (PBx) in the initial and repeated setting is still an issue of controversy. We performed an analysis of the recent literature about the prostate biopsy techniques.

METHODS

We performed a clinical and critical literature review by searching MEDLINE database from January 2005 up to January 2014. Electronic searches were limited to the English language, and the keywords prostate cancer, prostate biopsy, transrectal ultrasound, transperineal prostate biopsy were used.

RESULTS

Prostate biopsy strategy in initial setting. According to the literature and the major international guidelines, the recommended approach in initial setting is still the extended scheme (EPBx) (12 cores). However, there is now a growing evidence in the literature that (a) saturation PBx (>20 cores) (SPBx) might be indicated in patients with PSA <10 ng/ml or low PSA density or large prostate and (b) an individualized approach with more than 12 cores according to the clinical characteristics of the patients may optimize cancer detection in the single patient. Moreover, in the era of multi-parametric MRI (mpMRI), EPBx or SPBX may be substituted by mpMRI-targeted biopsies that have demonstrated superiority over systematic random biopsies for the detection of clinically significant disease and representation of disease burden, while deploying fewer cores. Prostate biopsy strategy in repeat setting. How and how many cores should be taken in the different scenarios in the repeated setting is still unclear. SPBx clearly improves cancer detection if clinical suspicion persists after previous biopsy with negative findings and is able to provide an accurate prediction of prostate tumour volume and grade. Nevertheless, international guidelines do not strongly recommended SPBx in all situations of repeated setting. In the active surveillance and in focal therapy protocols, the optimal schemes have to be defined.

CONCLUSIONS

The course of PBx has changed significantly from sextant biopsies to systematic and from extended to SPBx schemes. The issue about the number and location of the cores is still a matter of debate both in initial and in repeat setting. At present, EPBx is sufficient in most of the cases to provide adequate diagnosis and prostate cancer characterization in the initial setting, while SPBx seems to be necessary in repeat setting. The PBx schemes are evolving also because the scenario in which a PBx is necessary is changing. Random prostate PBx do not represent the future, while imaging target biopsy are becoming more popular.

Optimization of prostate biopsy: review of technique and complications

A 12-core systematic biopsy that incorporates apical and far-lateral cores in the template distribution allows maximal cancer detection and avoidance of a repeat biopsy while minimizing the detection of insignificant prostate cancers. Magnetic resonance imaging-guided prostate biopsy has an evolving role in both initial and repeat prostate biopsy strategies, potentially improving sampling efficiency, increasing the detection of clinically significant cancers, and reducing the detection of insignificant cancers. Hematuria, hematospermia, and rectal bleeding are common complications of prostate needle biopsy, but are generally self-limiting and well tolerated. All men should receive antimicrobial prophylaxis before biopsy.

Prostate biopsy for the interventional radiologist

Prostate biopsies are usually performed by urologists in the office setting using transrectal ultrasound (US) guidance. The current standard of care involves obtaining 10-14 cores from different anatomic sections. Biopsies are usually not directed into a specific lesion because most prostate cancers are not visible on transrectal US. Color Doppler, US contrast agents, elastography, magnetic resonance (MR) imaging, and MR imaging/US fusion are proposed as imaging methods to guide prostate biopsies. Prostate MR imaging and fusion biopsy create opportunities for diagnostic and interventional radiologists to play an increasingly important role in the screening, evaluation, diagnosis, targeted biopsy, surveillance, and focal therapy of patients with prostate cancer.

Comparison of 8, 10, 12, 16, 20 cores prostate biopsies in the determination of prostate cancer and the importance of prostate volume

INTRODUCTION

In this study, we evaluate the relationship between increasing core numbers and cancer detection rate.

METHODS

We included 1120 patients with prostate-specific antigen levels ≤20 ng/mL and/or suspicious digital rectal examination findings in this study. All patients had a first-time prostate biopsy and 8, 10, 12, 16, and 20 core biopsies were taken and examined in different groups during the study. Multiple logistic regression analysis was made to reach the factor affecting the cancer detection rate between the patients with and without cancer. A p < 0.05 was considered statistically significant.

RESULTS

Out of 1120 patients, 221 (19.7%) had prostate cancer. Again of the total 1120 patients, 8 core biopsies were taken from 229 (20.4%); 10 core biopsies from 473 (42.2%); 12 core biopsies from 100 (8.9%); 16 core biopsies from 140 (12.5%); and 20 core biopsies from 178 (15.9%) patients. The increase in the core number increased the cancer detection rate by 1.06 times (p = 0.008).

CONCLUSIONS

As long as prostate volume increases, increasing the core number elevates the cancer detection rate. Thus, the rate of missed cancer will be reduced and the rates of unnecessary repetitive biopsy decreases.