Extended 12-core prostate biopsy increases both the detection of prostate cancer and the accuracy of Gleason score

Fewer systematic prostate core biopsies in clinical stage T1c prostate cancer leads to biochemical recurrence after brachytherapy as monotherapy

BACKGROUND

After brachytherapy, fewer prostate biopsy cores at diagnosis can underestimate the pathological characteristics of prostate cancer (PCa) with lower concordance, resulting in improper treatment, particularly in patients with low-risk nonpalpable cT1c PCa. The aim of this study was to assess the relationship between the number of biopsy cores at diagnosis and long-term clinical outcomes after brachytherapy for cT1c PCa.

METHODS

We reviewed 516 patients with localized cT1c PCa with Gleason scores of 3 + 3 = 6 or 3 + 4 = 7 who underwent brachytherapy as monotherapy without hormonal therapy between January 2005 and September 2014 at our institution. Clinical staging was based on the American Joint Committee on Cancer manual for staging. Thus, the cT1c category is based solely on digital rectal examination. The primary outcome was biochemical recurrence (BCR). Based on the optimized cutoff value for biopsy core number obtained from receiver operating characteristic analysis, patients were divided into the biopsy cores ≤8 (N = 123) and ≥9 (N = 393) groups. The BCR-free survival rate was compared between the groups. Prognostic factors for BCR were evaluated, including age, initial prostate-specific antigen (PSA) level, Gleason score, positive core rate, PSA density, prostate magnetic resonance imaging findings, and biopsy core number.

RESULTS

The median patient age was 66.0 years (interquartile range [IQR]: 61.0-71.0 years), and the median follow-up time was 11.1 years (IQR: 9.5-13.3 years). The median number of core biopsies was 12 (IQR: 9-12). The area under the curve was 0.637 (95% confidence interval [CI]: 0.53-0.75), and the optimal biopsy core cutoff value for BCR prediction was 8.5 (sensitivity = 43.5%, specificity = 77.1%). Although fewer patients had Gleason scores of 3 + 4 = 7 (19/123 [15%] vs. 125/393 [32%], p < 0.02) in the biopsy cores ≤8 group, the 10-year BCR-free survival rate was significantly lower in the biopsy cores ≤8 group than in the biopsy cores ≥9 group (93.8% vs. 96.3%, p < 0.05). Multivariate analysis revealed that a lower biopsy core number (hazard ratio: 0.828, 95% CI: 0.71-0.97, p < 0.03) and a Gleason score of 3 + 4 = 7 (hazard ratio: 3.26, 95% CI: 1.37-7.73, p < 0.01) significantly predicted BCR.

CONCLUSIONS

A low number of prostate core biopsies results in worse BCR-free survival after brachytherapy as monotherapy in patients with cT1c PCa.

Ethnic and regional differences in the temporal trends of prostate cancer incidence and mortality in New Zealand

BACKGROUND

Prostate cancer (Pca) is the most frequently diagnosed cancer in New Zealand (NZ) men and the third leading cause of cancer deaths. Temporal changes in Pca incidence and mortality have not been reported despite changes in the Pca landscape. This study aims to analyse the temporal trends in Pca with focus on ethnic and regional variations.

METHODS

The study cohort was identified from the NZ Cancer Registry and the mortality collection databases. Men who were diagnosed with Pca between 2000 and 2018 were included in the incidence analysis. Men who died from Pca between 2000 and 2015 were included in the mortality analysis. Other data collected were ethnicity and geographical information. Pca incidence and mortality were calculated as age-standardized rates using the 2001 World Health Organization population.

RESULTS

A total of 58 966 men were diagnosed (incidence: 105.2 per 100 000) and 14 749 men died (mortality: 49.3 per 100 000) from Pca. When compared to European men, Māori and Asian men had significantly lower Pca incidence. Mortality rates demonstrated a steady decline, which was more prominent until 2010. Māori and Pacific men had higher mortality rates when compared to European men. In most recent years, the difference in mortality is decreasing for Māori but increasing for Pacific men. There were no regional differences in mortality.

CONCLUSION

Pca incidence in NZ has fluctuated over the last 20 years, while mortality rates have shown to steadily decline. Pca mortality was shown to disproportionately affect Māori and Pacific men.

Dynamic Contrast-Enhanced MRI of Prostate Lesions of Simultaneous [68Ga]Ga-PSMA-11 PET/MRI: Comparison between Intraprostatic Lesions and Correlation between Perfusion Parameters

We aimed to retrospectively compare the perfusion parameters measured from dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) of prostate benign lesions and malignant lesions to determine the relationship between perfusion parameters. DCE-MRI was performed in patients with PCa who underwent simultaneous [68Ga]Ga-prostate-specific membrane antigen (PSMA)-11 positron emission tomography (PET)/MRI. Six perfusion parameters (arrival time (AT), time to peak (TTP), wash-in slope (W-in), wash-out slope (W-out), peak enhancement intensity (PEI), and initial area under the 60-s curve (iAUC)), and a semi-quantitative parameter, standardized uptake values maximum (SUVmax) were calculated by placing regions of interest in the largest area of the lesions. The DCE-MRI parameters between prostate benign and malignant lesions were compared. The DCE-MRI parameters in both the benign and malignant lesions subgroup with SUVmax ≤ 3.0 and SUVmax > 3.0 were compared. The correlation of DCE-MRI parameters was investigated. Malignant lesions demonstrated significantly shorter TTP and higher SUVmax than did benign lesions. In the benign and malignant lesions subgroup, perfusion parameters of lesions with SUVmax ≤ 3.0 show no significant difference to those with SUVmax > 3.0. DCE-MRI perfusion parameters show a close correlation with each other. DCE-MRI parameters reflect the perfusion characteristics of intraprostatic lesions with malignant lesions, demonstrating significantly shorter TTP. There is a moderate to strong correlation between DCE-MRI parameters. Semi-quantitative analysis reflects that malignant lesions show a significantly higher SUVmax than benign lesions.

Multiparametric Ultrasound for Targeting Prostate Cancer: Combining ARFI, SWEI, QUS and B-Mode

Diagnosing prostate cancer through standard transrectal ultrasound (TRUS)-guided biopsy is challenging because of the sensitivity and specificity limitations of B-mode imaging. We used a linear support vector machine (SVM) to combine standard TRUS imaging data with acoustic radiation force impulse (ARFI) imaging data, shear wave elasticity imaging (SWEI) data and quantitative ultrasound (QUS) midband fit data to enhance lesion contrast into a synthesized multiparametric ultrasound volume. This SVM was trained and validated using a subset of 20 patients and tested on a second subset of 10 patients. Multiparametric US led to a statistically significant improvements in contrast, contrast-to-noise ratio (CNR) and generalized CNR (gCNR) when compared with standard TRUS B-mode and SWEI; in contrast and CNR when compared with MF; and in CNR when compared with ARFI. ARFI, MF and SWEI also outperformed TRUS B-mode in contrast, with MF outperforming B-mode in CNR and gCNR as well. ARFI, although only yielding statistically significant differences in contrast compared with TRUS B-mode, captured critical qualitative features for lesion identification. Multiparametric US enhanced lesion visibility metrics and is a promising technique for targeted TRUS-guided prostate biopsy in the future.

Outcome of TRUS Biopsy with Limited Cores in Patients with PSA More Than 50 ng/dL: Can We Reduce the Number of Cores Without Affecting Outcomes?

The aims of our study were to see outcomes of limited core biopsy and compare its outcomes with standard 12-core biopsy in patients with PSA more than 50 ng/dL. We did a retrospective analysis of 149 patients undergoing prostatic biopsy with PSA more than 50 ng/dL between January 2014 and December 2018. Out of 149 patients, 49 underwent limited core (2 to 6 cores) TRUS biopsy with no systemic 12-core biopsy. Other 100 patients underwent standard 12-core biopsy under TRUS guidance. Total of 149 patient's records were analyzed and were included in the final analysis. There was no significant difference in demographics and prostate-specific antigen among the cohorts. All 49 patients in limited core TRUS biopsy had a positive biopsy with no need of re-biopsy. Fourteen out of 100 patients in TRUS biopsy had a negative biopsy. All 14 patients with negative biopsy had an average follow-up of 3.8 years with no conversion to positive biopsy. Patients with PSA more than 50 ng/dL and high clinical suspicion of prostate cancer can undergo limited core biopsy without systemic 12-core biopsy. In patients with no clinical evidence of prostate cancer, 12-core biopsy remains the gold standard for evaluation of prostate cancer.

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 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.

Cost-Effectiveness of Urinary Biomarker Panel in Prostate Cancer Risk Assessment

PURPOSE

SelectMDx (MDxHealth®) is a panel of urinary biomarkers used in conjunction with traditional risk factors to individualize risk prediction for clinically significant prostate cancer. In this study we sought to characterize the effectiveness of SelectMDx in a population of American men with elevated prostate specific antigen.

MATERIALS AND METHODS

We developed a Markov decision analytical model to simulate the chain of events and downstream outcomes associated with ultrasound guided prostate biopsy and a strategy in which the biomarker panel is implemented prior to biopsy. The primary outcome was health outcomes, measured in QALYs (quality-adjusted life years). The secondary outcome was health care costs from the Medicare payer perspective. Multiple 1-way sensitivity analyses were performed to characterize model robustness.

RESULTS

The expected mean QALYs per patient under the current standard was 10.796 at a cost of $11,060 during an 18-year horizon. Incorporating the urinary biomarker panel resulted in an expected mean of 10.841 QALYs per patient and a mean cost of $9,366, representing an average of 0.045 QALYs gained at a cost savings of $1,694 per patient. When extrapolating these data to a conservative estimate of 311,879 men per year undergoing biopsy, one would expect that the biomarker panel would result in an incremental 14,035 QALYs gained at a cost savings of $528,323,026 in each yearly cohort. The biomarker panel strategy dominated the current standard across a wide range of sensitivity analyses.

CONCLUSIONS

Routine use of the SelectMDx urinary biomarker panel to guide biopsy decision making improved health outcomes and lowered costs in American men at risk for prostate cancer. This strategy may optimize the value of prostate cancer risk assessment in an era of increasing financial accountability.

Cost-effectiveness of SelectMDx for prostate cancer in four European countries: a comparative modeling study

BACKGROUND

Low specificity of prostate-specific antigen results in a considerable number of unnecessary prostate biopsies in current practice. SelectMDx® predicts significant prostate cancer upon biopsy and is used to reduce the number of unnecessary initial prostate biopsies. Furthermore, potential overtreatment of insignificant prostate cancer can be reduced. Besides the diagnostic accuracy of the test, also the context in a specific country determines the potential health benefit and cost-effectiveness. Therefore, the health benefit and cost-effectiveness of SelectMDx were assessed in France, Germany, Italy, and Spain.

SUBJECT AND METHODS

A decision model was used to compare the current standard of care in which men undergo initial prostate biopsy in case of an elevated prostate-specific antigen, to a strategy in which SelectMDx was used to select men for biopsy. Model inputs most relevant to each of the four countries were obtained. With use of the model long-term quality-adjusted life years (QALYs) and healthcare costs were calculated for both strategies.

RESULTS

In all four countries, the SelectMDx resulted in QALY gain and cost savings compared with the current standard of care. In France, SelectMDx resulted in 0.022 QALYs gained and cost savings of €1217 per patient. For Germany, the model showed a QALY gain of 0.016 and a cost saving of €442. In Italy, the QALY gain and cost savings were 0.031 and €762. In Spain 0.020 QALYs were gained and €250 costs were saved.

CONCLUSIONS

The results of the model showed that with SelectMDx, QALYs could be gained while saving healthcare costs in the initial diagnosis of prostate cancer. The significant presence of overtreatment in the current standard of care in all four countries was the main factor that resulted in the beneficial outcomes with SelectMDx.

Role and Indications of Organ-Sparing "Radical" Cystectomy: The Importance of Careful Patient Selection and Counseling

Organ-sparing cystectomy remains an operation for a highly selected patient population that can offer similar oncologic outcomes but improved sexual function in men and women. Occult prostate cancer in men may occur even with screening but the majority is of clinical insignificance. Paramount to patient selection are oncologic concerns, but preoperative sexual function, age, performance status, and postoperative expectations must also be evaluated during patient selection. Improved diagnostic and surveillance tools may facilitate and improve patient selection in the future.

Accuracy of standardized 12-core template biopsies versus non-standardized biopsies for detection of Epstein Grade 5 prostate cancer regarding the histology of the prostatectomy specimen

OBJECTIVE

To evaluate the effectiveness of EAU Guideline compliant transrectal ultrasound-guided 12-core prostate biopsies for detection of highly aggressive Epstein Grade 5 (Gleason Score 9-10) prostate cancer.

METHODS

Two hundred ninety-nine patients, treated by radical prostatectomy for prostate cancer, have been prospectively recorded in a database and were evaluated for this study. Pre-operatively, all patients received transrectal ultrasound-guided biopsies according to inhomogeneous templates chosen by the referring urologist. We evaluated the outcomes according to a stratified group-analysis: Group 1 received less than 12 biopsies, Group 2 received more than 12 biopsies, and Group 3 received exactly 12 biopsies, according to the EAU Guidelines template. After surgical removal of the prostate, 12 EAU Guideline-templated biopsies were performed in all prostatectomy specimens, directly after the surgery. Pre-operative and post-operative Epstein Grade 5 biopsy detection rates were thereafter correlated with these prostatectomy specimens.

RESULTS

In prostatectomy specimens, the histology of 12 patients (4.0%) were Epstein Grade 1, 31 patients (10.5%) were Epstein Grade 2, 190 patients (63.5%) were Epstein Grade 3, 27 patients (9%) were Epstein Grade 4, and 39 patients (13%) were Epstein Grade 5. The detection rate of Epstein Grade 5 compared to the radical prostatectomy specimen was: Group 1: 23.0% pre-operatively and 61.5% post-operatively, Group 2: 33.3% pre-operatively and 58.3% post-operatively; and Group 3: 57.1% pre-operatively and 64.2% post-operatively.

CONCLUSION

Detection rates of highly aggressive Epstein Grade 5 prostate cancer vary considerably according to the biopsy technique. EAU Guideline compliant 12-core template biopsies increase the detection rates of Epstein Grade 5 prostate cancer.

RecQ helicase BLM regulates prostate cancer cell proliferation and apoptosis

Prostate cancer (PCa) is a common malignant tumor and the second leading cause of morbidity and mortality in men worldwide. Considering the prevalence and effects of PCa in males, an understanding of the molecular mechanisms underlying PCa tumorigenesis are essential and may provide novel therapeutic strategies for treating PCa. Bloom syndrome protein (BLM) is a member of the RecQ helicase family. The major function of BLM is to uncoil the double-stranded DNA structure. It has previously been demonstrated that BLM acts as a ‘genome caretaker’, and dysregulation of BLM function has been implicated in the development of multiple tumor types; however, its potential for inducing PCa tumorigenesis remains undetermined. The present study aimed to explore the function of BLM in PCa progression. Reverse transcription-polymerase chain reaction, immunohistochemistry and western blot analyses were performed to detect the BLM expression pattern in PCa patients and cell lines. The proliferation, and migration and invasion capacities of prostate cells were determined by EdU and Transwell assays following transfection with BLM-targeting short hairpin RNA (shRNA). The expression of BLM was significantly increased in PCa tissues and PC3 cells compared with non-PCa tissues and benign prostatic hyperplasia cells. Knockdown of BLM via shRNA inhibited PCa cell proliferation, and promoted PCa cell apoptosis. Notably, reducing the expression of BLM had no effect on the migration or invasive abilities of PCa cells. These results suggest that downregulation of BLM may alleviate PCa development, providing a novel perspective for PCa tumorigenesis and a potential therapeutic target for PCa.

Characteristics of prostate cancer detection rate (PCDR) in Chinese Han population under different prostate biopsy methods

We analyzed the improvement of prostate cancer detection rate (PCDR) in Chinese Han population and summarized the characteristics of prostate cancer (PCa) with the advancement of prostate biopsy technologies. From March 1999 to March 2015, 3762 patients underwent the systematic 6-, 8- or 13-core biopsy, guided by finger or transrectal ultrasound (TRUS) at our center. The PCDR under different PSA intervals and different biopsy methods were analyzed. The trends of PSA level, age and Gleason score of PCa patients were summarized. The PCDR of finger-guided 6- and 8-core biopsies were 30.8% (340/1103) and 36.7% (147/401) respectively. In 2258 patients with TRUS-guided 13-core biopsies, 992 (43.9%) were diagnosed as PCa, higher than that with finger-guided biopsies (43.9% vs. 32.4%, p < 0.001). The PCDR of prostate peripheral zone was higher than that of medial zone (37.5% vs. 31.4%, p < 0.001). Interestingly, the PCDR of extra 13th core was higher than the mean positive rate of other 12 cores (70.7% vs. 56.0%, p < 0.001). The systematic 13-core prostate biopsy guided by TRUS is safe, effective, and economic for PCa diagnosis in developing countries like China. The extra 13th core biopsy is beneficial to increase the PCDR.

Prospective comparison of the efficacy of caudal versus periprostatic nerve block, both with intrarectal local anesthesia, during transrectal ultrasonography-guided prostatic needle biopsy

OBJECTIVE

The aim of this study was to compare the effectiveness of caudal block (CB) versus periprostatic nerve block (PPNB), both with intrarectal local anesthesia (IRLA), in reducing pain during transrectal ultrasonography (TRUS)-guided prostatic biopsy.

MATERIALS AND METHODS

This study included 532 patients: 266 patients received CB with IRLA and 266 patients PPNB with IRLA. A visual analogue scale (VAS) was applied to prospectively evaluate pain (1) at induction of anesthesia, (2) at insertion of the TRUS probe, (3) at needle penetration to the prostate, and (4) throughout the biopsy procedure. Pain scores were compared to evaluate differences between groups. The secondary endpoint of serious complication rate was also evaluated. As a subanalysis, the pain scores were compared in patients with high body mass index (BMI ≥25 kg/m²).

RESULTS

Overall, the pain score in the PPNB group was significantly lower than in the CB group at induction of anesthesia (mean ± SD: 2.0 ± 1.9 vs 2.9 ± 2.1, p = .0001) but higher at insertion of the TRUS probe (2.7 ± 2.5 vs 1.9 ± 1.7, p = .009). The pain score did not differ significantly between groups at needle penetration or throughout the biopsy. Univariate analyses indicated no significant association between VAS scores and patient demographics. Overall rates of serious complications did not differ between the two groups (5.6% vs 5.3%, p = .85). In patients with high BMI, the pain score was significantly lower in the PPNB group than in the CB group throughout the procedure (2.5 ± 2.0 vs 3.5 ± 2.5, p = .03).

CONCLUSIONS

Both procedures were equally effective in reducing pain, and the incidence of serious complications was similar. PPNB with IRLA may be more applicable than CB with IRLA in obese patients.

Clinical performance of transperineal template guided mapping biopsy for therapeutic decision making in low risk prostate cancer

OBJECTIVES

To evaluate the role of Transperineal Template guided Mapping Biopsy (TTMB) in determining the management strategy in patients with low risk prostate cancer (PCa).

METHODS

We retroscpectively evaluated 169 patients who underwent TTMB at our institution from February 2008 to June 2011. Ninety eight of them harbored indolent PCa defined as: Prostate Specific Antigen<10ng/ml, Gleason score 6 or less, clinical stage T2a or less, unilateral disease and a maximum of one third positive cores at first biopsy and<50% of the core involved. TTMB results were analyzed for Gleason score upgrading and upstaging as compared to initial TransRectal UltraSound (TRUS) biopsies and its influence on the change in the treatment decisions.

RESULTS

TTMB detected cancer in 64 (65%) patients. The upgrade, upstage and both were noted in 33% (n=21), 12% (n=8) and 7% (n=5) respectively of the detected cancers. The disease characteristics was similar to initial TRUS in 30 (48%) patients and TTMB was negative in 34 (35%) patients. Prostate volume was significantly smaller in patients with upgrade and/or upstage noted at TTMB (45.4 vs 37.9; P=.03). TTMB results influenced 73.5% of upgraded and/or upstaged patients to receive radical treatment while 81% of the patients with unmodified stage and/or grade continued active surveillance or focal therapy.

CONCLUSIONS

In patients with low risk PCa diagnosed by TRUS, subsequent TTMB demonstrated cancer upgrade and/or upstage in about one-third of the patients and resulted in eventual change in treatment decision.

Visually Estimated MRI Targeted Prostate Biopsy Could Improve the Detection of Significant Prostate Cancer in Patients with a PSA Level <10 ng/mL

PURPOSE

To compare prostate cancer detection rates between 12 cores transrectal ultrasound-guided prostate biopsy (TRUS-Bx) and visually estimated multiparametric magnetic resonance imaging (mp-MRI)-targeted prostate biopsy (MRI-visual-Bx) for patients with prostate specific antigen (PSA) level less than 10 ng/mL.

MATERIALS AND METHODS

In total, 76 patients with PSA levels below 10 ng/mL underwent 3.0 Tesla mp-MRI and TRUS-Bx prospectively in 2014. In patients with abnormal lesions on mp-MRI, we performed additional MRI-visual-Bx. We compared pathologic results, including the rate of clinically significant prostate cancer cores (cancer length greater than 5 mm and/or any Gleason grade greater than 3 in the biopsy core).

RESULTS

The mean PSA was 6.43 ng/mL. In total, 48 of 76 (63.2%) patients had abnormal lesions on mp-MRI, and 116 targeted biopsy cores, an average of 2.42 per patient, were taken. The overall detection rates of prostate cancer using TRUS-Bx and MRI-visual-Bx were 26/76 (34.2%) and 23/48 (47.9%), respectively. In comparing the pathologic results of TRUS-Bx and MRI-visual-Bx cores, the positive rates were 8.4% (77 of 912 cores) and 46.6% (54 of 116 cores), respectively (p<0.001). Mean cancer core lengths and mean cancer core percentages were 3.2 mm and 24.5%, respectively, in TRUS-Bx and 6.3 mm and 45.4% in MRI-visual-Bx (p<0.001). In addition, Gleason score ≥7 was noted more frequently using MRI-visual-Bx (p=0.028). The detection rate of clinically significant prostate cancer was 27/77 (35.1%) and 40/54 (74.1%) for TRUS-Bx and MRI-visual-Bx, respectively (p<0.001).

CONCLUSION

MRI-visual-Bx showed better performance in the detection of clinically significant prostate cancer, compared to TRUS-Bx among patients with a PSA level less than 10 ng/mL.

Pathology and Quality of Life Outcomes Following Office-based Transperineal Prostate Biopsy

OBJECTIVE

To report the incidence of prostate cancer diagnosis and quality of life outcomes following transperineal prostate biopsy.

METHODS

Forty-six consecutive patients underwent office-based transperineal prostate biopsy for an elevated prostate-specific antigen and a normal digital rectal examination without prior prostate biopsy. Prior to biopsy, a repeat prostate-specific antigen was obtained to ensure persistent elevation. Silodosin (8 mg daily) was initiated the day prior to biopsy and continued for 1 week. A total of 18-20 biopsy cores were obtained per patient. All patients responded to a visual analog scale ranging from 0 to 10 immediately following the completion of both the local anesthesia and the biopsy procedure. In addition, an International Prostate Symptom Score (IPSS), Rectal Function Assessment Score, International Index of Erectile Function, Center for Epidemiologic Studies Depression Scale, and postvoid residual were obtained at baseline and 30 days following biopsy, except IPSS which was also obtained at day 7.

RESULTS

The mean patient age was 63.3 years with a mean prostate volume of 41.8 cm(3). The mean visual analog scale was 4.2 for the local anesthesia and 3.0 for the biopsy. Thirty-one patients (67.4%) were diagnosed with prostate cancer, with 18 having a Gleason score ≥ 7. Compared to baseline, no adverse changes in IPSS, Rectal Function Assessment Score, International Index of Erectile Function, Center for Epidemiologic Studies Depression Scale, or postvoid residual were detected at day 30. No patient required catheterization, developed sepsis, or required hospitalization.

CONCLUSION

Office-based transperineal prostate biopsy was well tolerated with reasonable treatment-related discomfort, a high rate of prostate cancer diagnosis, and the absence of significant morbidity including sepsis.

Diffusion-weighted imaging predicts upgrading of Gleason score in biopsy-proven low grade prostate cancers

OBJECTIVE

To analyse whether diffusion-weighted imaging (DWI) predicts Gleason score (GS) upgrading in biopsy-proven low grade prostate cancer (PCa).

PATIENTS AND METHODS

A total of 132 patients who had biopsy-proven low grade (GS < 7) PCa, 3T DWI results, and surgical confirmation were retrospectively included in the study. Clinical variables (prostate-specific antigen, greatest percentage of cancer in a biopsy core and percentage of positive cores) and DWI variables (minimum apparent diffusion coefficient [ADC_min ] and mean ADC [ADC_mean ]) were evaluated. ADC_min was measured, by two independent, blinded readers, using a region of interest (ROI) of 5-10 mm² at the area of lowest ADC value within a cancer, while ADC_mean was measured using an ROI covering more than half of a cancer. Logistic regression and receiver-operating characteristic curve analyses were performed.

RESULTS

The rate of GS upgrading was 46.1% (61/132). In both univariate and multivariate analyses, ADC_min and ADC_mean were persistently significant for predicting GS upgrading (P < 0.05), whereas clinical variables were not (P > 0.05). In both readers' results, the area under the curve (AUC) of ADC_min was significantly greater than that of ADC_mean (reader 1: AUC 0.760 vs 0.711; P < 0.001; reader 2: AUC 0.752 vs 0.714; P = 0.003).

CONCLUSION

Our results showed that DWI may predict GS upgrading of biopsy-proven low grade PCa. The variable ADC_min in PCa may perform better than ADC_mean .

Diagnosis of prostate cancer via nanotechnological approach

Prostate cancer is one of the leading causes of cancer-related deaths among the Caucasian adult males in Europe and the USA. Currently available diagnostic strategies for patients with prostate cancer are invasive and unpleasant and have poor accuracy. Many patients have been overly or underly treated resulting in a controversy regarding the reliability of current conventional diagnostic approaches. This review discusses the state-of-the-art research in the development of novel noninvasive prostate cancer diagnostics using nanotechnology coupled with suggested diagnostic strategies for their clinical implication.

Effect of patient position on pain scales during transrectal ultrasound-guided prostate biopsy

Purpose

Transrectal ultrasound (TRUS)-guided prostate biopsy is the most useful technique for the diagnosis of prostate cancer; however, many patients describe the procedure as uncomfortable and painful. We investigated the effect of the patient's position on pain scales during TRUS-guided prostate biopsy.

Materials and Methods

Between July 2012 and June 2013, a total of 128 consecutive patients who underwent TRUS-guided prostate biopsy were included in this study. Seventy patients underwent the procedure in the lithotomy position performed by a urologist and the other patients (n=58) underwent the procedure in the left lateral decubitus (LLD) position performed by a radiologist. Pain was assessed by using visual analogue scale (VAS) scores from 0 to 10. Using a linear regression model, we analyzed the correlation between pain scale score and clinical variables with a focus on patient position.

Results

No significant differences related to age, body mass index, prostate volume, prostate-specific antigen (PSA), hematuria, pyuria, International Prostate Symptom Score, or the cancer detection rate were observed between the lithotomy and the LLD groups. In the correlation analysis, VAS score showed a significant correlation with diabetes mellitus, PSA level, and lithotomy position (p<0.05). In the multiple linear regression model, VAS score showed a significant correlation with lithotomy position (β=-0.772, p=0.003) and diabetes mellitus (β=-0.803, p=0.033).

Conclusions

We suggest that the lithotomy position may be the proper way to reduce pain during TRUS-guided prostate biopsy.

MRI-based prostate volume-adjusted prostate-specific antigen in the diagnosis of prostate cancer

PURPOSE

To determine whether prostate-specific antigen (PSA) levels adjusted by prostate and zonal volumes estimated from magnetic resonance imaging (MRI) improve the diagnosis of prostate cancer (PCa) and differentiation between patients who harbor high-Gleason-sum PCa and those without PCa.

MATERIALS AND METHODS

This retrospective study was Health Insurance Portability and Accountability Act (HIPAA)-compliant and approved by the Institutional Review Board of participating medical institutions. T2 -weighted MR images were acquired for 61 PCa patients and 100 patients with elevated PSA but without PCa. Computer methods were used to segment prostate and zonal structures and to estimate the total prostate and central-gland (CG) volumes, which were then used to calculate CG volume fraction, PSA density, and PSA density adjusted by CG volume. These quantities were used to differentiate patients with and without PCa. Area under the receiver operating characteristic curve (AUC) was used as the figure of merit.

RESULTS

The total prostate and CG volumes, CG volume fraction, and PSA density adjusted by the total prostate and CG volumes were statistically significantly different between patients with PCa and patients without PCa (P ≤ 0.007). AUC values for the total prostate and CG volumes, and PSA density adjusted by CG volume, were 0.68 ± 0.04, 0.68 ± 0.04, and 0.66 ± 0.04, respectively, and were significantly better than that of PSA (P < 0.02), for differentiation of PCa patients from patients without PCa.

CONCLUSION

The total prostate and CG volumes estimated from T2 -weighted MR images and PSA density adjusted by these volumes can improve the effectiveness of PSA for the diagnosis of PCa and differentiation of high-Gleason-sum PCa patients from patients without PCa.

The prognostic value of reactive stroma on prostate needle biopsy: a population-based study

BACKGROUND

Reactive tumor stroma has been shown to play an active role in prostatic carcinogenesis. A grading system for reactive stroma in prostate cancer (PC) has recently been established and found to predict biochemical recurrence and prostate cancer-specific mortality (PCSM) in prostatectomized patients. To the best of our knowledge, there has been no study investigating the prognostic value of reactive stromal grading (RSG) with regard to PCSM when evaluated in diagnostic prostate needle biopsies.

METHODS

A population-based study on 318 patients, encompassing all cases of PC diagnosed by needle biopsies and without evidence of systemic metastasis at the time of diagnosis in Aust-Agder County in the period 1991-1999. Patients were identified by cross-referencing the Cancer Registry of Norway. Clinical data were obtained by review of medical charts. The endpoint was PCSM. RSG was evaluated on haematoxylin and eosin stained sections according to previously described criteria; grade 0, 0-5% reactive stroma; grade 1, 6-15%; grade 2, 16-50%; grade 3, 51-100%.

RESULTS

RSG could be evaluated in 278 patients. The median follow- up time was 110 months (interquartile range: 51-171). The 10-year PC - specific survival rate for RSGs of 0, 1, 2, and 3 was 96%, 81%, 69%, and 63%, respectively (P < 0.005). RSG remained independently associated with PCSM in a multivariate Cox regression analysis adjusting for prostate-specific antigen level, clinical stage, Gleason score, and mode of treatment. The concordance index of the multivariate model was 0.814 CONCLUSIONS: Our study demonstrates that RSG in diagnostic prostate needle biopsies predicts PCSM independently of other evaluable prognostic factors. Hence, RSG could be used in addition to traditional prognostic factors for prognostication and treatment stratification of PC patients.

When prostate cancer remains undetectable: The dilemma

Since the first report on the efficacy of sextant biopsy under transrectal ultrasound guidance, there have been many modifications related to the total number of cores and the localization of biopsies to improve the prostate cancer (PCa) detection rate. The 2010 National Comprehensive Cancer Network Early PCa Detection Guidelines noted the 12-core biopsy scheme as the standard. However, this extended biopsy scheme still fails to detect 20% of high-grade PCa that can be detected by detailed pathological evaluation of radical prostatectomy; therefore, there is need for saturation biopsies. The existence of suspicions of PCa after previous negative biopsy or biopsies represents a valid indication for saturation biopsy. There has been no significant increment in morbidity or in insignificant PCa detection rates when a saturation biopsy scheme was used with an extended biopsy scheme. Along with the improvement in the PCa detection rate, accurate oncological mapping of PCa is another important consideration of saturation biopsies. The ideal number of cores and the diagnostic value of saturation biopsy after the failure of initial therapy are some of the issues that need to be addressed. Preliminary reports have shown that magnetic resonance imaging can improve the PCa detection rate, save patients from unnecessary biopsies, and decrease the need for a high number of cores; however, multiple limitations continue to exist.

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.

Systematic 12- and 13-core transrectal ultrasound- or magnetic resonance imaging-guided biopsies significantly improve prostate cancer detection rate: A single-center 13-year experience

The aim of the present study was to evaluate the value of systematic 12- and 13-core biopsies, guided by transrectal ultrasound (TRUS) or magnetic resonance imaging (MRI), with regard to the prostate cancer detection rate (PCDR). Between July 1999 and June 2012, 2,707 patients were recruited to the Department of Urology, The First Affiliated Hospital of Nanjing Medical University (Nanjing, China). Prostate biopsies were performed via systematic 12- or 13-core biopsy and guided by either TRUS or MRI. The PCDR was established by retrospectively analyzing the distribution of positive cores, and it was assumed that all patients had undergone four biopsy schemes: Medial 6-core, lateral 6-core, 12-core and entire 13-core. In addition, the positive rate of the biopsies with the extra 13th core and the mean positive rate of systematic 12-core biopsies were compared. The PCDR of an entire 13-core biopsy was significantly higher than that of a lateral 6-core biopsy. The positive rate of the extra 13th core, which identified abnormal TRUS or MRI findings, was significantly higher when compared with that of the mean positive rate of the systematic 12-core biopsy. The results of the present study demonstrated that the entire 13-core biopsy was superior to the 6-core biopsy with regard to the PCDR. Therefore, the systematic 12-core biopsy with an extra 13th core is considered to be beneficial towards improving the PCDR.

Optimizing prostate specimen handling for diagnosis and prognosis

Optimal processing, handling, and sampling of prostatic biopsies, transurethral resections, and radical prostatectomy specimens ensure accurate diagnosis and staging. Prognostic factors derived from careful examination of tissue samples are critical for patient management, including cancer volume, extraprostatic extension, surgical margins, vascular/lymphatic invasion, and perineural invasion. This chapter addresses these important issues, including recent recommendations of a consensus panel of the International Society of Urologic Pathologists.

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.

Cancer detection rates of different prostate biopsy regimens in patients with renal failure

We aimed to evaluate the cancer detection rates of 6-, 10-, 12-core biopsy regimens and the optimal biopsy protocol for prostate cancer diagnosis in patients with renal failure. A total of 122 consecutive patients with renal failure underwent biopsy with age-specific prostate-specific antigen (PSA) levels up to 20 ng/mL. The 12-core biopsy technique (sextant biopsy + lateral base, lateral mid-zone, lateral apex, bilaterally) performed to all patients. Pathology results were examined separately for each sextant, 10-core that exclude parasagittal mid-zones from 12-cores (10a), 10-core that exclude apex zones from 12-cores (10b) and 12-core biopsy regimens. Of 122 patients, 37 (30.3%) were positive for prostate cancer. The cancer detection rates for sextant, 10a, 10b and 12 cores were 17.2%, 29%, 23.7% and 30.7%, respectively. Biopsy techniques of 10a, 10b and 12 cores increased the cancer detection rates by 40%, 27.5% and 43.2% among the sextant technique, respectively. Biopsy techniques of 10a and 12 cores increased the cancer detection rates by 17.1% and 21.6% among 10b biopsy technique, respectively. There were no statistical differences between 12 core and 10a core about cancer detection rate. Adding lateral cores to sextant biopsy improves the cancer detection rates. In our study, 12-core biopsy technique increases the cancer detection rate by 5.4% among 10a core but that was not statistically different. On the other hand, 12-core biopsy technique includes all biopsy regimens. We therefore suggest 12-core biopsy or minimum 10-core strategy incorporating six peripheral biopsies with elevated age- specific PSA levels up to 20 ng/mL in patients with renal failure.

Evaluation of short-TE (1)H MRSI for quantification of metabolites in the prostate

Back-to-back (1)H MRSI scans, using an endorectal and phased-array coil combination, were performed on 18 low-risk patients with prostate cancer at 3 T, employing TEs of 32 and 100 ms in order to compare metabolite visualization at each TE. Outer-volume suppression of lipid signals was performed using regional saturation (REST) slabs and the quantification of spectra at both TEs was achieved with the quantitation using quantum estimation (QUEST) routine. Metabolite nulling experiments in an additional five patients found that there were negligible macromolecule background signals in prostate spectra at TE = 32 ms. Metabolite visibility was judged using the criterion Cramér-Rao lower bound (CRLB)/amplitude < 20%, and metabolite concentrations were corrected for relaxation effects and referenced to the data acquired in corresponding water-unsuppressed MRSI scans. For the first time, the prostate metabolites spermine and myo-inositol were quantified individually in vivo, together with citrate, choline and creatine. All five metabolite visibilities were higher in TE = 32 ms MRSI than in TE = 100 ms MRSI. At TE = 32 ms, citrate was visible in 99.0% of lipid-free spectra, whereas, at TE = 100 ms, no metabolite simulation of citrate matched the in vivo peaks. Spermine, choline and creatine were visualised separately in 30.4% more spectra at TE = 32 ms than at TE = 100 ms, and myo-inositol in 72.5% more spectra. T2 values were calculated for spermine (53 ± 16 ms), choline (62 ± 17 ms) and myo-inositol (90 ± 48 ms). Data from the TE = 32 ms spectra showed that the concentrations of citrate and spermine secretions were positively correlated in both the peripheral zone and central gland (R(2)  = 0.73 and R(2)  = 0.43, respectively), and that the citrate content was significantly higher in the former at 64 ± 22 mm than in the latter at 32 ± 16 mm (p = 0.01). However, lipid contamination at TE = 32 ms was substantial; therefore, to make clinical use of the greater visualisation of prostate metabolites at TE = 32 ms rather than at TE = 100 ms, three-dimensional MRSI at TE = 32 ms with effective lipid suppression must be implemented.

The effect of differing Gleason scores at biopsy on the odds of upgrading and the risk of death from prostate cancer

INTRODUCTION/BACKGROUND

The GS is an established prostate cancer prognostic factor. Whether the presence of differing GSs at biopsy (eg, 4+3 and 3+3), which we term ComboGS, improves the prognosis that would be predicted based on the highest GS (eg, 4+3) because of decreased upgrading is unknown. Therefore, we evaluated the odds of upgrading at time of radical prostatectomy (RP) and the risk of PCSM when ComboGS was present versus absent.

PATIENTS AND METHODS

Logistic and competing risks regression were performed to assess the effect that ComboGS had on the odds of upgrading at time of RP in the index (n = 134) and validation cohorts (n = 356) and the risk of PCSM after definitive therapy in a long-term cohort (n = 666), adjusting for known predictors of these end points. We calculated and compared the area under the curve using a receiver operating characteristic analysis when ComboGS was included versus excluded from the upgrading models.

RESULTS

ComboGS was associated with decreased odds of upgrading (index: adjusted odds ratio [AOR], 0.14; 95% confidence interval [CI], 0.04-0.50; P = .003; validation: AOR, 0.24; 95% CI, 0.11-0.51; P < .001) and added significantly to the predictive value of upgrading for the in-sample index (P = .02), validation (P = .003), and out-of-sample prediction models (P = .002). ComboGS was also associated with a decreased risk of PCSM (adjusted hazard ratio, 0.40; 95% CI, 0.19-0.85; P = .02).

CONCLUSION

Differing biopsy GSs are associated with a lower odds of upgrading and risk of PCSM. If validated, future randomized noninferiority studies evaluating deescalated treatment approaches in men with ComboGS could be considered.

Transperineal ultrasound-guided 12-core prostate biopsy: an extended approach to diagnose transition zone prostate tumors

Objective

Transperineal ultrasound-guided (TPUS) 12-core prostate biopsy was evaluated as an initial strategy for the diagnosis of prostate cancer, The distribution of prostate cancer lesions was assessed with zone-specific biopsy.

Methods

From January 2010 to December 2012, 287 patients underwent TPUS-guided 12-core prostate biopsy. Multiple cores were obtained from both the peripheral zone (PZ) and the transition zone (TZ) of the prostate. Participants' clinical data and the diagnostic yield of the cores were recorded and prospectively analyzed as a cross-sectional study.

Results

The diagnostic yield of the 12-core prostate biopsy was significantly higher compared to the 6-core scheme (42.16 vs. 21.6%). The diagnostic yield of the 10-core prostate biopsy was significantly higher compared to the 6-core scheme (37.6 vs. 21.6%). The 12-core scheme improved the diagnostic yield in prostates >50 ml (12-core scheme: 28.1% vs. 10-core scheme: 20.4%; p = 0.034).

Conclusions

The 12-core biopsy scheme is a safe and effective approach for the diagnosis of prostate cancer. TZ biopsies in patients with larger prostates should be included in the initial biopsy strategy.

Cost-effectiveness of magnetic resonance (MR) imaging and MR-guided targeted biopsy versus systematic transrectal ultrasound-guided biopsy in diagnosing prostate cancer: a modelling study from a health care perspective

BACKGROUND

The current diagnostic strategy using transrectal ultrasound-guided biopsy (TRUSGB) raises concerns regarding overdiagnosis and overtreatment of prostate cancer (PCa). Interest in integrating multiparametric magnetic resonance imaging (MRI) and magnetic resonance-guided biopsy (MRGB) into the diagnostic pathway to reduce overdiagnosis and improve grading is gaining ground, but it remains uncertain whether this image-based strategy is cost-effective.

OBJECTIVE

To determine the cost-effectiveness of multiparametric MRI and MRGB compared with TRUSGB.

DESIGN, SETTING, AND PARTICIPANTS

A combined decision tree and Markov model for men with elevated prostate-specific antigen (>4 ng/ml) was developed. Input data were derived from systematic literature searches, meta-analyses, and expert opinion.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Quality-adjusted life years (QALYs) and health care costs of both strategies were modelled over 10 yr after initial suspicion of PCa. Probabilistic and threshold analyses were performed to assess uncertainty.

RESULTS AND LIMITATIONS

Despite uncertainty around the presented cost-effectiveness estimates, our results suggest that the MRI strategy is cost-effective compared with the standard of care. Expected costs per patient were € 2423 for the MRI strategy and € 2392 for the TRUSGB strategy. Corresponding QALYs were higher for the MRI strategy (7.00 versus 6.90), resulting in an incremental cost-effectiveness ratio of € 323 per QALY. Threshold analysis revealed that MRI is cost-effective when sensitivity of MRGB is ≥ 20%. The probability that the MRI strategy is cost-effective is around 80% at willingness to pay thresholds higher than € 2000 per QALY.

CONCLUSIONS

Total costs of the MRI strategy are almost equal with the standard of care, while reduction of overdiagnosis and overtreatment with the MRI strategy leads to an improvement in quality of life.

PATIENT SUMMARY

We compared costs and quality of life (QoL) of the standard "blind" diagnostic technique with an image-based technique for men with suspicion of prostate cancer. Our results suggest that costs were comparable, with higher QoL for the image-based technique.

Optimization of initial prostate biopsy in clinical practice: sampling, labeling and specimen processing

PURPOSE

An optimal prostate biopsy in clinical practice is based on a balance among adequate detection of clinically significant prostate cancers (sensitivity), assuredness regarding the accuracy of negative sampling (negative predictive value), limited detection of clinically insignificant cancers and good concordance with whole gland surgical pathology results to allow accurate risk stratification and disease localization for treatment selection. Inherent within this optimization is variation of the core number, location, labeling and processing for pathological evaluation. To date, there is no consensus in this regard. The purpose of this review is to 1) define the optimal number and location of biopsy cores during primary prostate biopsy among men with suspected prostate cancer, 2) define the optimal method of labeling prostate biopsy cores for pathological processing which will provide relevant and necessary clinical information for all potential clinical scenarios, and 3) determine the maximal number of prostate biopsy cores allowable within a specimen jar which would not preclude accurate histological evaluation of the tissue.

MATERIALS AND METHODS

A bibliographic search using PubMed® covering the period up to July 2012 yielded approximately 550 articles. Articles were reviewed and categorized based on which of the 3 objectives of this review was addressed. Data were extracted, analyzed and summarized. Recommendations are provided based on this literature review and our clinical experience.

RESULTS

The use of 10 to 12-core extended sampling protocols increases cancer detection rates compared to traditional sextant sampling methods and reduces the likelihood of repeat biopsy by increasing negative predictive value, ultimately allowing more accurate risk stratification without increasing the likelihood of detecting insignificant cancers. As the number of cores increases above 12, the increase in diagnostic yield becomes marginal. Only limited evidence supports the use of initial biopsy schemes involving more than 12 cores or saturation. Apical and laterally directed sampling of the peripheral zone increases cancer detection rate, reduces the need for repeat biopsies and predicts pathological features on prostatectomy while transition zone biopsies do not. There are little data to suggest that knowing the exact site of an individual positive biopsy core provides meaningful clinical information. However, determining laterality of cancer on biopsy may be helpful for predicting sites of extracapsular extension and therapeutic planning. Placement of multiple biopsy cores in a single container (greater than 2) appears to compromise pathological evaluation, which can reduce cancer detection rate and increase the likelihood of equivocal diagnoses.

CONCLUSIONS

A 12-core systematic biopsy that incorporates apical and far-lateral cores in the template distribution allows maximal cancer detection, avoids repeat biopsy, and provides information adequate for identifying men who need therapy and planning that therapy while minimizing the detection of occult, indolent prostate cancers. This literature review does not provide compelling evidence that individual site specific labeling of cores benefits clinical decision making regarding the management of prostate cancer. Based on the available literature, we recommend packaging no more than 2 cores in each jar to avoid reduction of the cancer detection rate through inadequate tissue sampling.

Combined application of information theory on laboratory results with classification and regression tree analysis: analysis of unnecessary biopsy for prostate cancer

BACKGROUND

The probability of a prostate cancer-positive biopsy result varies with PSA concentration. Thus, we applied information theory on classification and regression tree (CART) analysis for decision making predicting the probability of a biopsy result at various PSA concentrations.

METHODS

From 2007 to 2009, prostate biopsies were performed in 664 referred patients in a tertiary hospital. We created 2 CART models based on the information theory: one for moderate uncertainty (PSA concentration: 2.5-10 ng/ml) and the other for high uncertainty (PSA concentration: 10-25 ng/ml).

RESULTS

The CART model for moderate uncertainty (n=321) had 3 splits based on PSA density (PSAD), hypoechoic nodules, and age and the other CART for high uncertainty (n=160) had 2 splits based on prostate volume and percent-free PSA. In this validation set, the patients (14.3% and 14.0% for moderate and high uncertainty groups, respectively) could avoid unnecessary biopsies without false-negative results.

CONCLUSIONS

Using these CART models based on uncertainty information of PSA, the overall reduction in unnecessary prostate biopsies was 14.0-14.3% and CART models were simplified. Using uncertainty of laboratory results from information theoretic approach can provide additional information for decision analysis such as CART.

Findings in 12-core transrectal ultrasound-guided prostate needle biopsy that predict more advanced cancer at prostatectomy: analysis of 388 biopsy-prostatectomy pairs

We analyzed 5 features on 12-core transrectal ultrasound-guided prostate needle biopsy (TRUS) to predict the extent of cancer at radical prostatectomy (RP). In 388 TRUS-RP pairs, number of positive cores (NPC), percentage of each core involved (%PC), perineural invasion (PNI), Gleason score (GS), distribution of positive cores (DPC), and preoperative prostate-specific antigen (PSA) were correlated with extraprostatic extension (EPE), seminal vesicle invasion (SVI), positive surgical margin (R1), positive lymph nodes (N1), and tumor volume. All features predicted EPE and SVI. NPC, GS, %PC, and PNI strongly predicted R1 status. RP tumor volume was directly proportional to the NPC and %PC. PSA alone and with selected biopsy findings correlated with tumor volume, stage, SVI, and N1 (P < .0001). Contiguous DPC was a significant risk for EPE and SVI (P < .0001) compared with isolated positive cores. Findings at 12-core TRUS along with preoperative PSA reliably predict advanced local disease and have practical value as guides to effective planning for surgical resections.

Current perspectives on Gleason grading of prostate cancer

The 5-tier Gleason grading system for prostate cancer, introduced in 1966, has been proven to be one of the main independent predictors of prostate cancer outcome. This review addresses interobserver concordance in Gleason grading; the persistence of grading discrepancies with frequent upgrading from the biopsy to the prostatectomy specimen; the 2005 International Society of Urologic Pathologists' modifications to Gleason grading; the impact of this modified grading on grade migration and outcome prediction; and molecular correlates of cancer morphology. Data from the most recent years are emphasized.

Underestimation of Gleason score at prostate biopsy reflects sampling error in lower volume tumours

OBJECTIVE

• To determine the influence of tumour and prostate gland volumes on the underestimation of prostate cancer Gleason score in diagnostic core biopsies.

PATIENTS AND METHODS

• Patients undergoing radical prostatectomy with matched diagnostic biopsies were identified from a prospectively recorded database. • Tumour volumes were measured in serial whole-mount sections with image analysis software as part of routine histological assessment. • Differences in various metrics of tumour and prostate volume between upgraded tumours and tumours concordant for the lower or higher grade were analysed.

RESULTS

• In all, 684 consecutive patients with Gleason score 6 or 7 prostate cancer on diagnostic biopsy were identified. • Of 298 patients diagnosed with Gleason 6 tumour on biopsy, 201 (67.4%) were upgraded to Gleason 7 or higher on final pathology. Similarly, of 262 patients diagnosed with Gleason 3 + 4 = 7 prostate cancer on initial biopsy, 60 (22.9%) were upgraded to Gleason score 4 + 3 = 7 or higher. • Tumours upgraded from Gleason 6 to 7 had a significantly lower index tumour volume (1.73 vs 2 mL, P= 0.029), higher calculated prostate volume (41.6 vs 39 mL, P= 0.017) and lower relative percentage of tumour to benign glandular tissue (4.3% vs 5.9%, P= 0.001) than tumours concordant for the higher grade. • Similarly, tumours that were Gleason score 3 + 4 on biopsy and upgraded on final pathology to 4 + 3 were significantly smaller as measured by both total tumour volume (2.3 vs 3.3 mL, P= 0.005) and index tumour volume (2.2 vs 3, P= 0.027) and occupied a smaller percentage of the gland volume (6.3% vs 8.9%, P= 0.017) compared with tumours concordant for the higher grade. • On multivariate analysis, lower prostate weight (hazard ratio 0.97, 95% confidence interval 0.96-0.99, P < 0.001) and larger total tumour volume (hazard ratio 1.87, 95% confidence interval 1.4-2.6, P < 0.001) independently predicted an upgrade in Gleason score from 6 to 7. In tumours upgraded from biopsy Gleason 3 + 4, only higher index tumour volume (hazard ratio 3.1, 95% confidence interval 1.01-9.3, P= 0.048) was a significant predictor of upgrading on multivariate analysis.

CONCLUSIONS

• Under-graded tumours are significantly smaller than tumours concordant for the higher grade, indicating that incomplete tumour sampling plays a significant role in Gleason score assignment error. • Surrogate measures of tumour volume may predict those at greatest risk of Gleason score upgrade.

Predictors for clinically relevant Gleason score upgrade in patients undergoing radical prostatectomy

OBJECTIVE

To evaluate clinical predictors for Gleason score upgrade (GSU) in radical prostatectomy (RP) specimen, especially in patients with 'very' low risk PCA (T1c and biopsy Gleason score ≤6 and PSA <10 ng/ml and ≤2 positive biopsy cores and PSA density <0.15).

PATIENTS AND METHODS

402 consecutive patients undergoing RP between 2004 and 2006, including a subgroup of 62 patients with 'very' low risk PCA, were examined. Patients were categorized for clinically relevant GSU (defined as upgrade into a higher PCA risk category). Parameters including number of biopsy cores obtained, positive biopsy cores, prostate weight, PSA, DRE and pathology department were evaluated for their role as predictors. Furthermore, GSU in RP specimen was analyzed for its impact on pT-stage.

RESULTS

Clinically relevant GSU occurred in 38.1% in the whole cohort and in 32.3% in the 'very' low risk PCA subgroup. Gleason score downgrade (GSD) occurred in 4.7%. Number of biopsy cores obtained and prostate weight were independent negative predictors of GSU in all 402 patients (P = 0.02 and P = 0.03, respectively). In the 'very' low risk group, only number of biopsy cores obtained revealed as an independent negative predictor of GSU (P = 0.02). PSA, DRE, number of positive cores or pathology department were not associated to GSU. In the 'very' low risk group, GSU was related with extracapsular tumor extension (P = 0.05).

CONCLUSIONS

Clinically relevant GSU in RP specimen is still a challenging problem. Increasing the number of biopsy cores lower this risk significantly. GSD is rare and thus of minor importance for treatment decisions.

Percentage of free prostate-specific antigen: implications in modern extended scheme prostate biopsy

OBJECTIVES

To validate the performance of percentage of free prostate-specific antigen (%fPSA) in men undergoing extended scheme biopsy. The current cutoff values for %fPSA were chosen using data from sextant biopsies, which have been known to miss a significant number of prostate cancer cases. Additionally, we sought to validate the use of %fPSA in men with a total PSA < 4.0 ng/mL or > 10.0 ng/mL.

METHODS

We evaluated %fPSA performance in 1077 men who had undergone initial extended prostate biopsy. The men were categorized according to their PSA level into 2 groups (>4.0 and ≤4.0) ng/mL.

RESULTS

The overall cancer detection rate was 42.1%. The mean PSA level was 7.6 ng/mL, and the mean %fPSA was 18.0%. The area under the curve for %fPSA was 0.59 (95% confidence interval 0.57-0.61) for all PSA levels, comparable to previous reports from sextant biopsy series. The performance of %fPSA in predicting prostate cancer on initial extended biopsy was improved with a PSA level of ≤4.0 ng/mL (area under the curve 0.66, 95% confidence interval 0.62-0.70) compared with a PSA level >4.0 ng/mL (area under the curve 0.57, 95% confidence interval 0.55-0.59; P < .001). A specificity of 85% was achieved for a %fPSA cutoff of 11% for the ≤4.0-ng/mL group and 10% for the >4.0-ng/mL group.

CONCLUSIONS

The performance of %fPSA in predicting the presence of prostate cancer was not altered when an extended biopsy scheme was used. Although a %fPSA level greater than our cutoffs would not rule out prostate cancer, a low %fPSA would be particularly useful in predicting prostate cancer, especially in men with normal digital rectal examination findings and a PSA level <4 ng/mL.

Characterizing stiffness of human prostates using acoustic radiation force

Acoustic Radiation Force Impulse (ARFI) imaging has been previously reported to portray normal anatomic structures and pathologies in ex vivo human prostates with good contrast and resolution. These findings were based on comparison with histological slides and McNeal's zonal anatomy. In ARFI images, the central zone (CZ) appears darker (smaller displacement) than other anatomic zones and prostate cancer (PCa) is darker than normal tissue in the peripheral zone (PZ). Since displacement amplitudes in ARFI images are determined by both the underlying tissue stiffness and the amplitude of acoustic radiation force that varies with acoustic attenuation, one question that arises is how the relative displacements in prostate ARFI images are related to the underlying prostatic tissue stiffness. In linear, isotropic elastic materials and in tissues that are relatively uniform in acoustic attenuation (e.g., liver), relative displacement in ARFI images has been shown to be correlated with underlying tissue stiffness. However, the prostate is known to be heterogeneous. Variations in acoustic attenuation of prostatic structures could confound the interpretation of ARFI images due to the associated variations in the applied acoustic radiation force. Therefore, in this study, co-registered three-dimensional (3D) ARFI datasets and quantitative shear wave elasticity imaging (SWEI) datasets were acquired in freshly-excised human prostates to investigate the relationship between displacement amplitudes in ARFI prostate images and the matched reconstructed shear moduli. The lateral time-to-peak (LTTP) algorithm was applied to the SWEI data to compute the shear-wave speed and reconstruct the shear moduli. Five types of prostatic tissue (PZ, CZ, transition zone (TZ) and benign prostatic hyperplasia (BPH), PCa and atrophy) were identified, whose shear moduli were quantified to be 4.1 +/- 0.8 kPa, 9.9 +/- 0.9 kPa, 4.8 +/- 0.6 kPa, 10.0 +/- 1.0 kPa and 8.0 kPa, respectively. Linear regression was performed to compare ARFI displacement amplitudes and the inverse of the corresponding reconstructed shear moduli at multiple depths. The results indicate an inverse relation between ARFI displacement amplitude and reconstructed shear modulus at all depths. These findings support the conclusion that ARFI prostate images portray underlying tissue stiffness variations.

Pathologic results of radical prostatectomies in patients with simultaneous atypical small acinar proliferation and prostate cancer

PURPOSE

The incidence of adenocarcinoma on a subsequent biopsy following a diagnosis of atypical small acinar proliferation (ASAP) ranges from 34% to 60%. We reexamined radical prostatectomy (RP) specimens of patients diagnosed as having synchronous ASAP with prostate cancer (PCa) to evaluate pathological entities and the clinical significance of ASAP.

MATERIALS AND METHODS

From January 2007 to December 2008, a total of 118 patients who had been diagnosed with adenocarcinoma on prostate needle biopsy underwent RP. Forty-six of the 118 patients (39%) were diagnosed as having synchronous ASAP with PCa on the prostate needle biopsy. Using whole-mount sections and prostate mapping, we evaluated the RP specimens that were close sections to the ASAP on prostate needle biopsy. All tissues were examined by immunohistochemistry with high molecular weight cytokeratin (34betaE12), p63, and AMACR/P504S added to initial H&E stains by one pathologist.

RESULTS

Thirty-six of the 46 patients (78%) were diagnosed as having adenocarcinoma at sites of ASAP on the initial prostate needle biopsies. The Gleason score was 5 to 6 in 22 patients (61%), 7 in 3 (8%), and unknown due to multifocal and microfocal lesions in 11 (31%). The tumor volume of 14 of the 36 patients (39%) was 0.5 cc or less and was unknown due to multifocal and microfocal lesions in 8 (22%).

CONCLUSIONS

Most ASAP on initial prostate needle biopsy was a true pathological entity, in other words, prostatic adenocarcinoma. Aggressive approaches including more extended repeat biopsy with additional biopsy of the site of the ASAP are needed to diagnose PCa in patients with ASAP.

Acoustic radiation force impulse imaging of human prostates ex vivo

It has been challenging for clinicians using current imaging modalities to visualize internal structures and detect lesions inside human prostates. Lack of contrast among prostatic tissues and high false positive or negative detection rates of prostate lesions have limited the use of current imaging modalities in the diagnosis of prostate cancer. In this study, acoustic radiation force impulse (ARFI) imaging is introduced to visualize the anatomical and abnormal structures in freshly excised human prostates. A modified Siemens Antares ultrasound scanner (Siemens Medical Solutions USA Inc., Malvern, PA) and a Siemens VF10-5 linear array were used to acquire ARFI images. The transducer was attached to a three-dimensional (3-D) translation stage, which was programmed to automate volumetric data acquisition. A depth dependent gain (DDG) method was developed and applied to 3-D ARFI datasets to compensate for the displacement gradients associated with spatially varying radiation force magnitudes as a function of depth. Nine human prostate specimens were collected and imaged immediately after surgical excision. Prostate anatomical structures such as seminal vesicles, ejaculatory ducts, peripheral zone, central zone, transition zone and verumontanum were visualized with high spatial resolution and in good agreement with McNeal's zonal anatomy. The characteristic appearance of prostate pathologies, such as prostate cancerous lesions, benign prostatic hyperplasia, calcified tissues and atrophy were identified in ARFI images based upon correlation with the corresponding histologic slides. This study demonstrates that ARFI imaging can be used to visualize internal structures and detecting suspicious lesions in the prostate and appears promising for image guidance of prostate biopsy.

Effect of the number of biopsy cores on prostate cancer detection and staging

Digital rectal examination, serum concentration of prostate cancer-specific antigen and transrectal ultrasound-guided biopsies are currently the main diagnostic tools to detect evidence of prostate cancer. Different prostatic biopsy strategies have been proposed in order to achieve an optimal prostate cancer detection rate and an accurate characterization of prostate cancer stage and grade. We examined the role of the number of biopsy cores on prostate cancer detection rates at initial and repeat biopsies. Moreover, we examined the relationship between the number of biopsy cores and the detection of insignificant prostate cancer. Finally, we reviewed the ability of biopsy cores in predicting prostate cancer stage and grade at radical prostatectomy. We relied on a PubMed systematic review of the contemporary English language literature using the terms ‘prostate cancer’, ‘diagnosis’, ‘transrectal ultrasound’ and ‘prostate biopsy’.