Regional Histopathology and Prostate MRI Positivity: A Secondary Analysis of the PROMIS Trial.

Background The effects of regional histopathologic changes on prostate MRI scans have not been accurately quantified in men with an elevated prostate-specific antigen (PSA) level and no previous biopsy. Purpose To assess how Gleason grade, maximum cancer core length (MCCL), inflammation, prostatic intraepithelial neoplasia (PIN), or atypical small acinar proliferation within a Barzell zone affects the odds of MRI visibility. Materials and Methods In this secondary analysis of the Prostate MRI Imaging Study (PROMIS; May 2012 to November 2015), consecutive participants who underwent multiparametric MRI followed by a combined biopsy, including 5-mm transperineal mapping (TPM), were evaluated. TPM pathologic findings were reported at the whole-prostate level and for each of 20 Barzell zones per prostate. An expert panel blinded to the pathologic findings reviewed MRI scans and declared which Barzell areas spanned Likert score 3-5 lesions. The relationship of Gleason grade and MCCL to zonal MRI outcome (visible vs nonvisible) was assessed using generalized linear mixed-effects models with random intercepts for individual participants. Inflammation, PIN, and atypical small acinar proliferation were similarly assessed in men who had negative TPM results. Results Overall, 161 men (median age, 62 years [IQR, 11 years]) were evaluated and 3179 Barzell zones were assigned MRI status. Compared with benign areas, the odds of MRI visibility were higher when a zone contained cancer with a Gleason score of 3+4 (odds ratio [OR], 3.1; 95% CI: 1.9, 4.9; P < .001) or Gleason score greater than or equal to 4+3 (OR, 8.7; 95% CI: 4.5, 17.0; P < .001). MCCL also determined visibility (OR, 1.24 per millimeter increase; 95% CI: 1.15, 1.33; P < .001), but odds were lower with each prostate volume doubling (OR, 0.7; 95% CI: 0.5, 0.9). In men who were TPM-negative, the presence of PIN increased the odds of zonal visibility (OR, 3.7; 95% CI: 1.5, 9.1; P = .004). Conclusion An incremental relationship between cancer burden and prostate MRI visibility was observed. Prostatic intraepithelial neoplasia contributed to false-positive MRI findings. ClinicalTrials.gov registration no. NCT01292291 © RSNA, 2022 Supplemental material is available for this article. See also the editorial by Harmath in this issue.

False Positive Multiparametric Magnetic Resonance Imaging Phenotypes in the Biopsy-naïve Prostate: Are They Distinct from Significant Cancer-associated Lesions? Lessons from PROMIS.

BACKGROUND: False positive multiparametric magnetic resonance imaging (mpMRI) phenotypes prompt unnecessary biopsies. The Prostate MRI Imaging Study (PROMIS) provides a unique opportunity to explore such phenotypes in biopsy-naïve men with raised prostate-specific antigen (PSA) and suspected cancer. OBJECTIVE: To compare mpMRI lesions in men with/without significant cancer on transperineal mapping biopsy (TPM). DESIGN, SETTING, AND PARTICIPANTS: PROMIS participants (n=235) underwent mpMRI followed by a combined biopsy procedure at University College London Hospital, including 5-mm TPM as the reference standard. Patients were divided into four mutually exclusive groups according to TPM findings: (1) no cancer, (2) insignificant cancer, (3) definition 2 significant cancer (Gleason ≥3+4 of any length and/or maximum cancer core length ≥4mm of any grade), and (4) definition 1 significant cancer (Gleason ≥4+3 of any length and/or maximum cancer core length ≥6mm of any grade). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Index and/or additional lesions present in 178 participants were compared between TPM groups in terms of number, conspicuity, volume, location, and radiological characteristics. RESULTS AND LIMITATIONS: Most lesions were located in the peripheral zone. More men with significant cancer had two or more lesions than those without significant disease (67% vs 37%; p< 0.001). In the former group, index lesions were larger (mean volume 0.68 vs 0.50 ml; p< 0.001, Wilcoxon test), more conspicuous (Likert 4-5: 79% vs 22%; p< 0.001), and diffusion restricted (mean apparent diffusion coefficient [ADC]: 0.73 vs 0.86; p< 0.001, Wilcoxon test). In men with Likert 3 index lesions, log2PSA density and index lesion ADC were significant predictors of definition 1/2 disease in a logistic regression model (mean cross-validated area under the receiver-operator characteristic curve: 0.77 [95% confidence interval: 0.67-0.87]). CONCLUSIONS: Significant cancer-associated MRI lesions in biopsy-naïve men have clinical-radiological differences, with lesions seen in prostates without significant disease. MRI-calculated PSA density and ADC could predict significant cancer in those with indeterminate MRI phenotypes. PATIENT SUMMARY: Magnetic resonance imaging (MRI) lesions that mimic prostate cancer but are, in fact, benign prompt unnecessary biopsies in thousands of men with raised prostate-specific antigen. In this study we found that, on closer look, such false positive lesions have different features from cancerous ones. This means that doctors could potentially develop better tools to identify cancer on MRI and spare some patients from unnecessary biopsies.

A critical evaluation of visual proportion of Gleason 4 and maximum cancer core length quantified by histopathologists.

Gleason score 7 prostate cancer with a higher proportion of pattern 4 (G4) has been linked to genomic heterogeneity and poorer patient outcome. The current assessment of G4 proportion uses estimation by a pathologist, with a higher proportion of G4 more likely to trigger additional imaging and treatment over active surveillance. This estimation method has been shown to have inter-observer variability. Fifteen patients with Prostate Grade Group (GG) 2 (Gleason 3 + 4) and fifteen patients with GG3 (Gleason 4 + 3) disease were selected from the PROMIS study with 192 haematoxylin and eosin-stained slides scanned. Two experienced uropathologists assessed the maximum cancer core length (MCCL) and G4 proportion using the current standard method (visual estimation) followed by detailed digital manual annotation of each G4 area and measurement of MCCL (planimetric estimation) using freely available software by the same two experts. We aimed to compare visual estimation of G4 and MCCL to a pathologist-driven digital measurement. We show that the visual and digital MCCL measurement differs up to 2 mm in 76.6% (23/30) with a high degree of agreement between the two measurements; Visual gave a median MCCL of 10 ± 2.70 mm (IQR 4, range 5-15 mm) compared to digital of 9.88 ± 3.09 mm (IQR 3.82, range 5.01-15.7 mm) (p = 0.64) The visual method for assessing G4 proportion over-estimates in all patients, compared to digital measurements [median 11.2% (IQR 38.75, range 4.7-17.9%) vs 30.4% (IQR 18.37, range 12.9-50.76%)]. The discordance was higher as the amount of G4 increased (Bias 18.71, CI 33.87-48.75, r 0.7, p < 0.0001). Further work on assessing actual G4 burden calibrated to clinical outcomes might lead to the use of differing G4 thresholds of significance if the visual estimation is used or by incorporating semi-automated methods for G4 burden measurement.

What Type of Prostate Cancer Is Systematically Overlooked by Multiparametric Magnetic Resonance Imaging? An Analysis from the PROMIS Cohort.

BACKGROUND: All risk stratification strategies in cancer overlook a spectrum of disease. The Prostate MR Imaging Study (PROMIS) provides a unique opportunity to explore cancers that are overlooked by multiparametric magnetic resonance imaging (mpMRI). OBJECTIVE: To summarise attributes of cancers that are systematically overlooked by mpMRI. DESIGN, SETTING, AND PARTICIPANTS: PROMIS tested performance of mpMRI and transrectal ultrasonography (TRUS)-guided biopsy, using 5 mm template mapping (TPM) biopsy as the reference standard. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Outcomes were overall and maximum Gleason scores, maximum cancer core length (MCCL), and prostate-specific antigen density (PSAD). Cancer attributes were compared between cancers that were overlooked and those that were detected. RESULTS AND LIMITATIONS: Of men with cancer, 7% (17/230; 95% confidence interval [CI] 4.4-12%) had significant disease overlooked by mpMRI according to definition 1 (Gleason ≥ 4 + 3 of any length or MCCL ≥ 6 mm of any grade) and 13% (44/331; 95% CI 9.8-17%) according to definition 2 (Gleason ≥ 3 + 4 of any length or MCCL ≥ 4 mm). In comparison, TRUS-guided biopsy overlooked 52% (119/230; 95% CI 45-58%) of significant disease by definition 1 and 40% (132/331; 95% CI 35-45%) by definition 2. Prostate cancers undetected by mpMRI had significantly lower overall and maximum Gleason scores (p = 0.0007; p < 0.0001) and shorter MCCL (median difference: 3 mm [5 vs 8 mm], p < 0.0001; 95% CI 1-3) than cancers that were detected. No tumours with overall Gleason score > 3 + 4 (Gleason Grade Groups 3-5; 95% CI 0-6.4%) or maximum Gleason score > 4 + 3 (Gleason Grade Groups 4-5; 95% CI 0-8.0%) on TPM biopsy were undetected by mpMRI. Application of a PSAD threshold of 0.15 reduced the proportion of men with undetected cancer to 5% (12/230; 95% CI 2.7-8.9%) for definition 1 and 9% (30/331; 95% CI 6.2-13%) for definition 2. Application of a PSAD threshold of 0.10 reduced the proportion of men with undetected disease to 3% (6/230; 95% CI 1.0-5.6%) for definition 1 cancer and to 3% (11/331; 95% CI 1.7-5.9%) for definition 2 cancer. Limitations were post hoc analysis and uncertain significance of undetected lesions. CONCLUSIONS: Overall, a small proportion of cancers are overlooked by mpMRI, with estimates ranging from 4.4% (lower boundary of 95% CI for definition 1) to 17% (upper boundary of 95% CI for definition 2). Prostate cancers undetected by mpMRI are of lower grade and shorter length than cancers that are detected. PATIENT SUMMARY: Prostate cancers that are undetected by magnetic resonance imaging (MRI) are smaller and less aggressive than those that are detected, and none of the most aggressive cancers are overlooked by MRI.

Additional Value of Dynamic Contrast-enhanced Sequences in Multiparametric Prostate Magnetic Resonance Imaging: Data from the PROMIS Study.

BACKGROUND: Multiparametric magnetic resonance imaging (MP-MRI) is established in the diagnosis of prostate cancer, but the need for enhanced sequences has recently been questioned. OBJECTIVE: To assess whether dynamic contrast-enhanced imaging (DCE) improves accuracy over T2 and diffusion sequences. DESIGN, SETTING, AND PARTICIPANTS: PROMIS was a multicentre, multireader trial, with, in this part, 497 biopsy-naïve men undergoing standardised 1.5T MP-MRI using T2, diffusion, and DCE, followed by a detailed transperineal prostate mapping (TPM) biopsy at 5 mm intervals. Likert scores of 1-5 for the presence of a significant tumour were assigned in strict sequence, for (1) T2 + diffusion and then (2) T2 + diffusion + dynamic contrast-enhanced images. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: For the primary analysis, the primary PROMIS outcome measure (Gleason score ≥4 + 3 or ≥6 mm maximum cancer length) on TPM was used, and an MRI score of ≥3 was considered positive. RESULTS AND LIMITATIONS: Sensitivity without and with DCE was 94% and 95%, specificity 37% and 38%, positive predictive value 51% and 51%, and negative predictive value 90% and 91%, respectively (p > 0.05 in each case). The number of patients avoiding biopsy (scoring 1-2) was similar (123/497 vs 121/497, p = 0.8). The number of equivocal scores (3/5) was slightly higher without DCE (32% vs 28% p = 0.031). The proportion of MRI equivocal (3/5) and positive (4-5) cases showing significant tumours were similar (23% and 71% vs 20% and 69%). No cases of dominant Gleason 4 or higher were missed with DCE, compared with a single case with T2 + diffusion-weighted imaging. No attempt was made to correlate lesion location on MRI and histology, which may be considered a limitation. Radiologists were aware of the patient's prostate-specific antigen. CONCLUSIONS: Contrast adds little when MP-MRI is used to exclude significant prostate cancer. PATIENT SUMMARY: An intravenous injection of contrast may not be necessary when magnetic resonance imaging is used as a test to rule out significant tumours in the prostate.

Comparison of Transrectal Ultrasound Biopsy to Transperineal Template Mapping Biopsies Stratified by Multiparametric Magnetic Resonance Imaging Score in the PROMIS Trial.

PURPOSE: We evaluated the performance of transrectal ultrasound guided systematic and transperineal template mapping biopsies with a 5 mm sampling frame stratified by the multiparametric magnetic resonance imaging Likert score in the PROMIS (Prostate MR Imaging Study). MATERIALS AND METHODS: Biopsy naïve men due to undergo prostate biopsy for elevated prostate specific antigen and/or abnormal digital rectal examination underwent multiparametric magnetic resonance imaging, and transperineal template mapping and transrectal ultrasound guided systematic biopsies, which were performed and reported while blinded to other test results. Clinically significant prostate cancer was primarily defined as Gleason 4 + 3 or greater, or a maximum cancer core length of 6 mm or more of any grade. It was secondarily defined as Gleason 3 + 4 or greater, or a maximum cancer core length of 4 mm or more of any grade. RESULTS: In 41 months 740 men were recruited at a total of 11 centers, of whom 576 underwent all 3 tests. Eight of the 150 men (5.1%) with a multiparametric magnetic resonance imaging score of 1-2 had any Gleason 3 + 4 or greater disease on transrectal ultrasound guided systematic biopsy. Of the 75 men in whom transrectal ultrasound guided systematic biopsy showed Gleason 3 + 3 of any maximum cancer core length 61 (81%) had Gleason 3 + 4, 8 (11%) had Gleason 4 + 3 and 0 (0%) had Gleason 4 + 5 or greater disease. For definition 1 (clinically significant prostate cancer) transrectal ultrasound guided systematic biopsy sensitivity remained stable and low across multiparametric magnetic resonance imaging Likert scores of 35% to 52%. For definition 2 (clinically significant prostate cancer and any cancer) sensitivity increased with higher multiparametric magnetic resonance imaging scores. The negative predictive value varied due to varying disease prevalence but for all cancer thresholds it declined with increasing multiparametric magnetic resonance imaging scores. CONCLUSIONS: In the setting of multiparametric magnetic resonance imaging Likert scores 1-2 transrectal ultrasound guided systematic biopsy revealed Gleason 3 + 4 disease in only 1 of 20 men. Further, for any clinically significant prostate cancer definition transrectal ultrasound guided systematic biopsy had poor sensitivity and variable but a low negative predictive value across multiparametric magnetic resonance imaging scores. Men who undergo transrectal ultrasound guided systematic biopsy without targeting in the setting of a multiparametric magnetic resonance imaging score of 3 to 5 should be advised to undergo repeat (targeted) biopsy.

A Multicentre Analysis of the Detection of Clinically Significant Prostate Cancer Following Transperineal Image-fusion Targeted and Nontargeted Systematic Prostate Biopsy in Men at Risk.

BACKGROUND: Prostate biopsy guided by magnetic resonance imaging (MRI) is increasingly used to obtain tissue from men with suspected prostate cancer (PC). OBJECTIVE: To report a multicentre series of image-fusion transperineal prostate biopsies and compare the diagnostic yield of clinically significant PC (csPC) between targeted and nontargeted biopsies. DESIGN, SETTING, AND PARTICIPANTS: The study included 640 consecutive patients with elevated prostate specific antigen (PSA) presenting for first biopsy or following a previous negative transrectal biopsy under the care of 13 urologists in 11 centres in the UK (April 2014-June 2017). INTERVENTION: Multiparametric MRI was carried out in 61 approved prostate MRI centres with transperineal targeted alone (n=283) or targeted plus nontargeted (n=357) transperineal rigid image-fusion targeted biopsy (MIM-Symphony-DX). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Rates of csPC and insignificant cancer detection in targeted and nontargeted biopsies were measured using a number of thresholds to define clinical significance. The primary definition was Gleason≥4+3 or any grade ≥6mm. RESULTS AND LIMITATIONS: The mean age, median PSA, and median prostate volume for the cohort were 63.8yr (standard deviation [SD] 8.4), 6.3 ng/ml (SD 5.8), and 42.0cm3 (SD 24.7), respectively. Overall, 276/640 men (43.1%) were diagnosed with csPC. csPC was detected from targeted biopsies alone in 263/640 cases (41.1%). Of the 357 men who underwent nontargeted biopsies, three (0.8%) had csPC exclusively in nontargeted cores, with no evidence of cancer in targeted cores. Overall, 32/357 (9.0%) had csPC in nontargeted biopsies regardless of the targeted biopsy findings. Clinically insignificant disease in nontargeted biopsies was detected in 93/357 men (26.1%). Our findings were consistent across all other thresholds of clinical significance. Limitations include the lack of nontargeted biopsies in all men. CONCLUSIONS: In this large multicentre series, nontargeted prostate biopsy cores had a low yield of csPC and a high yield of clinically insignificant PC. An image-fusion targeted-biopsy-only approach maintains high detection for csPC and low detection of clinically insignificant cancers. PATIENT SUMMARY: In this report, we found that following prostate multiparametric magnetic resonance imaging and targeted transperineal biopsies of suspicious areas, the clinical value of performing additional extensive unguided biopsies of nonsuspicious areas is limited and can often find insignificant cancers that do not need treatment.

Focal High-intensity Focussed Ultrasound Partial Gland Ablation for the Treatment of Localised Prostate Cancer: A Report of Medium-term Outcomes From a Single-center in the United Kingdom.

OBJECTIVE: To report our intermediate outcomes of the use of focal ablation for treating significant unilateral prostate cancer. This technique was adopted in our center 10 years ago. With improving diagnostic accuracy of index prostate cancer lesions and a low side-effect profile, use of focal high intensity focused ultrasound (HIFU) ablation is increasing. METHODS: Patients were diagnosed using prostate specific antigen (PSA), multiparametric magnetic resonance imaging, and template transperineal biopsies. Focal ablation of significant cancer was performed with the Sonablate device. Follow-up consisted of magnetic resonance imaging scanning, PSA, validated questionnaires, biopsy for cause, and redo HIFU if required as part of the treatment strategy. RESULTS: A total of 107 men underwent focal HIFU. In total, 88% had intermediate/high risk disease, and the mean pre-HIFU PSA was 7.7. A total of 31% had high volume Gleason 6 disease, 55% had Gleason 3+4 disease, and 13% had Gleason ≥ 4+3 disease. In total, 54 men received a hemiablation, 10 a focal ablation, and 43 a quadrant ablation. Median follow-up was 30 months, subjects' PSA dropped to an average 71% nadir. A total of 8% had biochemical recurrence and 11% required adjuvant treatment. Freedom from additional procedures for clinically significant recurrent disease, including redo-HIFU, was 85.5%. Postoperative complications included 1% new use of pads, 1.9% urethral stricture, 2.8% post-HIFU TURP, and new onset ED of 14%. CONCLUSION: In a carefully chosen cohort of patients for focal HIFU our results suggest acceptable oncological control with minimal postoperative morbidity. Further studies are required to establish this technique as a less morbid alternative to radical therapy.

Multiparametric MRI to improve detection of prostate cancer compared with transrectal ultrasound-guided prostate biopsy alone: the PROMIS study.

BACKGROUND: Men with suspected prostate cancer usually undergo transrectal ultrasound (TRUS)-guided prostate biopsy. TRUS-guided biopsy can cause side effects and has relatively poor diagnostic accuracy. Multiparametric magnetic resonance imaging (mpMRI) used as a triage test might allow men to avoid unnecessary TRUS-guided biopsy and improve diagnostic accuracy. OBJECTIVES: To (1) assess the ability of mpMRI to identify men who can safely avoid unnecessary biopsy, (2) assess the ability of the mpMRI-based pathway to improve the rate of detection of clinically significant (CS) cancer compared with TRUS-guided biopsy and (3) estimate the cost-effectiveness of a mpMRI-based diagnostic pathway. DESIGN: A validating paired-cohort study and an economic evaluation using a decision-analytic model. SETTING: Eleven NHS hospitals in England. PARTICIPANTS: Men at risk of prostate cancer undergoing a first prostate biopsy. INTERVENTIONS: Participants underwent three tests: (1) mpMRI (the index test), (2) TRUS-guided biopsy (the current standard) and (3) template prostate mapping (TPM) biopsy (the reference test). MAIN OUTCOME MEASURES: Diagnostic accuracy of mpMRI, TRUS-guided biopsy and TPM-biopsy measured by sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) using primary and secondary definitions of CS cancer. The percentage of negative magnetic resonance imaging (MRI) scans was used to identify men who might be able to avoid biopsy. RESULTS: Diagnostic study - a total of 740 men were registered and 576 underwent all three tests. According to TPM-biopsy, the prevalence of any cancer was 71% [95% confidence interval (CI) 67% to 75%]. The prevalence of CS cancer according to the primary definition (a Gleason score of ≥ 4 + 3 and/or cancer core length of ≥ 6 mm) was 40% (95% CI 36% to 44%). For CS cancer, TRUS-guided biopsy showed a sensitivity of 48% (95% CI 42% to 55%), specificity of 96% (95% CI 94% to 98%), PPV of 90% (95% CI 83% to 94%) and NPV of 74% (95% CI 69% to 78%). The sensitivity of mpMRI was 93% (95% CI 88% to 96%), specificity was 41% (95% CI 36% to 46%), PPV was 51% (95% CI 46% to 56%) and NPV was 89% (95% CI 83% to 94%). A negative mpMRI scan was recorded for 158 men (27%). Of these, 17 were found to have CS cancer on TPM-biopsy. Economic evaluation - the most cost-effective strategy involved testing all men with mpMRI, followed by MRI-guided TRUS-guided biopsy in those patients with suspected CS cancer, followed by rebiopsy if CS cancer was not detected. This strategy is cost-effective at the TRUS-guided biopsy definition 2 (any Gleason pattern of ≥ 4 and/or cancer core length of ≥ 4 mm), mpMRI definition 2 (lesion volume of ≥ 0.2 ml and/or Gleason score of ≥ 3 + 4) and cut-off point 2 (likely to be benign) and detects 95% (95% CI 92% to 98%) of CS cancers. The main drivers of cost-effectiveness were the unit costs of tests, the improvement in sensitivity of MRI-guided TRUS-guided biopsy compared with blind TRUS-guided biopsy and the longer-term costs and outcomes of men with cancer. LIMITATIONS: The PROstate Magnetic resonance Imaging Study (PROMIS) was carried out in a selected group and excluded men with a prostate volume of > 100 ml, who are less likely to have cancer. The limitations in the economic modelling arise from the limited evidence on the long-term outcomes of men with prostate cancer and on the sensitivity of MRI-targeted repeat biopsy. CONCLUSIONS: Incorporating mpMRI into the diagnostic pathway as an initial test prior to prostate biopsy may (1) reduce the proportion of men having unnecessary biopsies, (2) improve the detection of CS prostate cancer and (3) increase the cost-effectiveness of the prostate cancer diagnostic and therapeutic pathway. The PROMIS data set will be used for future research; this is likely to include modelling prognostic factors for CS cancer, optimising MRI scan sequencing and biomarker or translational research analyses using the blood and urine samples collected. Better-quality evidence on long-term outcomes in prostate cancer under the various management strategies is required to better assess cost-effectiveness. The value-of-information analysis should be developed further to assess new research to commission. TRIAL REGISTRATION: Current Controlled Trials ISRCTN16082556 and NCT01292291. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 39. See the NIHR Journals Library website for further project information. This project was also supported and partially funded by the NIHR Biomedical Research Centre at University College London (UCL) Hospitals NHS Foundation Trust and UCL and by The Royal Marsden NHS Foundation Trust and The Institute of Cancer Research Biomedical Research Centre and was co-ordinated by the Medical Research Council's Clinical Trials Unit at UCL (grant code MC_UU_12023/28). It was sponsored by UCL. Funding for the additional collection of blood and urine samples for translational research was provided by Prostate Cancer UK.

Prostate cancer detection using quantitative T2 and T2 -weighted imaging: The effects of 5-alpha-reductase inhibitors in men on active surveillance.

BACKGROUND: T2 -weighted imaging (T2 -WI) information has been used in a qualitative manner in the assessment of prostate cancer. Quantitative derivatives (T2 relaxation time) can be generated from T2 -WI. These outputs may be useful in helping to discriminate clinically significant prostate cancer from background signal. PURPOSE/HYPOTHESIS: To investigate changes in quantitative T2 parameters in lesions and noncancerous tissue of men on active surveillance for prostate cancer taking dutasteride 0.5 mg or placebo daily for 6 months. STUDY TYPE: Retrospective. POPULATION/SUBJECTS: Forty men randomized to 6 months of daily dutasteride (n = 20) or placebo (n = 20). FIELD STRENGTH/SEQUENCE: Multiparametric 3T MRI at baseline and 6 months. This included a multiecho MR sequence for quantification of the T2 relaxation times, in three regions of interest (index lesion, noncancerous peripheral [PZ] and transitional [TZ] zones). A synthetic signal contrast (T2 Q contrast) between lesion and noncancerous tissue was assessed using quantitative T2 values. Signal contrast was calculated using the T2 -weighted sequence (T2 W contrast). ASSESSMENT: Two radiologists reviewed the scans in consensus according to Prostate Imaging Reporting and Data System (PI-RADS v. 2) guidelines. STATISTICAL TESTS: Wilcoxon and Mann-Whitney U-tests, Spearman's correlation. RESULTS: When compared to noncancerous tissue, shorter T2 values were observed within lesions at baseline (83.5 and 80.5 msec) and 6 months (81.5 and 81.9 msec) in the placebo and dutasteride arm, respectively. No significant differences for T2 W contrast at baseline and after 6 months were observed, both in the placebo (0.40 [0.29-0.49] vs. 0.43 [0.25-0.49]; P = 0.881) and dutasteride arm (0.35 [0.24-0.47] vs. 0.37 [0.22-0.44]; P = 0.668). There was a significant, positive correlation between the T2 Q contrast and the T2 W contrast values (r = 0.786; P < 0.001). DATA CONCLUSION: The exposure to antiandrogen therapy did not significantly influence the T2 contrast or the T2 relaxation values in men on active surveillance for prostate cancer. LEVEL OF EVIDENCE: 4 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1646-1653.

MRI findings in men on active surveillance for prostate cancer: does dutasteride make MRI visible lesions less conspicuous? Results from a placebo-controlled, randomised clinical trial.

OBJECTIVES: To investigate changes in the Apparent Diffusion Coefficient (ADC) using diffusion-weighted imaging (DWI) in men on active surveillance for prostate cancer taking dutasteride 0.5 mg or placebo. METHODS: We analysed 37 men, randomised to 6 months of daily dutasteride (n = 18) or placebo (n = 19), undergoing 3T multi-parametric Magnetic Resonance Imaging (mpMRI) scans at baseline and 6 months. Images were reviewed blind to treatment allocation and clinical information. Mean ADC of peripheral (PZ) and transition (TZ) zones, and MR-suspicious lesions were compared between groups over 6 months. Conspicuity was defined as the PZ divided by tumour ADC, and its change over 6 months was assessed. RESULTS: A decrease in mean conspicuity in the dutasteride group (but not the controls) was seen over 6 months (1.54 vs 1.38; p = 0.025). Absolute changes in ADC and conspicuity were significantly different between placebo and dutasteride groups at 6 months: (-0.03 vs 0.08, p = 0.033) and (0.11 vs -0.16, p = 0.012), as were percentage changes in the same parameters: (-2.27% vs 8.56% p = 0.048) and (9.25% vs -9.89% p = 0.013). CONCLUSIONS: Dutasteride was associated with increased tumour ADC and reduced conspicuity. A lower threshold for triggering biopsy might be considered in men on dutasteride undergoing mpMRI for prostate cancer. KEY POINTS: • Dutasteride increases ADC and reduces conspicuity in small mpMRI-visible prostate cancers. • Knowledge of dutasteride exposure is important in the interpretation of prostate mpMRI. • A lower threshold for triggering biopsy may be appropriate on dutasteride.

The Effect of Dutasteride on Magnetic Resonance Imaging Defined Prostate Cancer: MAPPED-A Randomized, Placebo Controlled, Double-Blind Clinical Trial.

PURPOSE: Dutasteride, which is licensed for symptomatic benign prostatic hyperplasia, has been associated with a lower progression rate of low risk prostate cancer. We evaluated the effect of dutasteride on prostate cancer volume as assessed by T2-weighted magnetic resonance imaging. MATERIALS AND METHODS: In this randomized, double-blind, placebo controlled trial, men with biopsy proven, low-intermediate risk prostate cancer (up to Gleason 3 + 4 and PSA up to 15 ng/ml) who had visible lesion of 0.2 ml or greater on T2-weighted magnetic resonance imaging sequences were randomized to daily dutasteride 0.5 mg or placebo for 6 months. Lesion volume was assessed at baseline, and 3 and 6 months with image guided biopsy to the lesion at study exit. The primary end point was the percent reduction in lesion volume over 6 months. This trial was registered with the European Clinical Trials register (EudraCT 2009-102405-18). RESULTS: A total of 42 men were recruited between June 2010 and January 2012. In the dutasteride group, the average volumes at baseline and 6 months were 0.55 and 0.38 ml, respectively and the average reduction was 36%. In the placebo group, the average volumes at baseline and 6 months were 0.65 and 0.76 ml, respectively, and the average reduction was -12%. The difference in percent reductions between the groups was 48% (95% CI 27.4-68.3, p <0.0001). The most common adverse event was deterioration in erectile function, which was 25% in men randomized to dutasteride and 16% in men randomized to placebo. CONCLUSIONS: Dutasteride was associated with a significant reduction in prostate cancer volume on T2-weighted magnetic resonance imaging compared to placebo.

Minimum 5-year follow-up of 1138 consecutive laparoscopic radical prostatectomies.

OBJECTIVES: To investigate the long-term outcomes of laparoscopic radical prostatectomy (LRP). PATIENTS AND METHODS: In all, 1138 patients underwent LRP during a 163-month period from 2000 to 2008, of which 51.5%, 30.3% and 18.2% were categorised into D'Amico risk groups of low-, intermediate- and high-risk, respectively. All intermediate- and high-risk patients were staged by preoperative magnetic resonance imaging or computed tomography and isotope bone scanning, and had a pelvic lymph node dissection (PLND), which was extended after April 2008. The median (range) patient age was 62 (40-78) years; body mass index was 26 (19-44) kg/m(2) ; prostate-specific antigen level was 7.0 (1-50) ng/mL and Gleason score was 6 (6-10). Neurovascular bundle was preservation carried out in 55.3% (bilateral 45.5%; unilateral 9.8%) of patients. RESULTS: The median (range) gland weight was 52 (14-214) g. The median (range) operating time was 177 (78-600) min and PLND was performed in 299 patients (26.3%), of which 54 (18.0%) were extended. The median (range) blood loss was 200 (10-1300) mL, postoperative hospital stay was 3 (2-14) nights and catheterisation time was 14 (1-35) days. The complication rate was 5.2%. The median (range) LN count was 12 (4-26), LN positivity was 0.8% and the median (range) LN involvement was 2 (1-2). There was margin positivity in 13.9% of patients and up-grading in 29.3% and down-grading in 5.3%. While 11.4% of patients had up-staging from T1/2 to T3 and 37.1% had down-staging from T3 to T2. One case (0.09%) was converted to open surgery and six patients were transfused (0.5%). At a mean (range) follow-up of 88.6 (60-120) months, 85.4% of patients were free of biochemical recurrence, 93.8% were continent and 76.6% of previously potent non-diabetic men aged <70 years were potent after bilateral nerve preservation. CONCLUSIONS: The long-term results obtainable from LRP match or exceed those previously published in large contemporary open and robot-assisted surgical series.

Focal therapy: patients, interventions, and outcomes--a report from a consensus meeting.

BACKGROUND: Focal therapy as a treatment option for localized prostate cancer (PCa) is an increasingly popular and rapidly evolving field. OBJECTIVE: To gather expert opinion on patient selection, interventions, and meaningful outcome measures for focal therapy in clinical practice and trial design. DESIGN, SETTING, AND PARTICIPANTS: Fifteen experts in focal therapy followed a modified two-stage RAND/University of California, Los Angeles (UCLA) Appropriateness Methodology process. All participants independently scored 246 statements prior to rescoring at a face-to-face meeting. The meeting occurred in June 2013 at the Royal Society of Medicine, London, supported by the Wellcome Trust and the UK Department of Health. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Agreement, disagreement, or uncertainty were calculated as the median panel score. Consensus was derived from the interpercentile range adjusted for symmetry level. RESULTS AND LIMITATIONS: Of 246 statements, 154 (63%) reached consensus. Items of agreement included the following: patients with intermediate risk and patients with unifocal and multifocal PCa are eligible for focal treatment; magnetic resonance imaging-targeted or template-mapping biopsy should be used to plan treatment; planned treatment margins should be 5mm from the known tumor; prostate volume or age should not be a primary determinant of eligibility; foci of indolent cancer can be left untreated when treating the dominant index lesion; histologic outcomes should be defined by targeted biopsy at 1 yr; residual disease in the treated area of ≤3 mm of Gleason 3+3 did not need further treatment; and focal retreatment rates of ≤20% should be considered clinically acceptable but subsequent whole-gland therapy deemed a failure of focal therapy. All statements are expert opinion and therefore constitute level 5 evidence and may not reflect wider clinical consensus. CONCLUSIONS: The landscape of PCa treatment is rapidly evolving with new treatment technologies. This consensus meeting provides guidance to clinicians on current expert thinking in the field of focal therapy. PATIENT SUMMARY: In this report we present expert opinion on patient selection, interventions, and meaningful outcomes for clinicians working in focal therapy for prostate cancer.

Determination of optimal drug dose and light dose index to achieve minimally invasive focal ablation of localised prostate cancer using WST11-vascular-targeted photodynamic (VTP) therapy.

OBJECTIVE: To determine the optimal drug and light dose for prostate ablation using WST11 (TOOKAD Soluble) for vascular-targeted photodynamic (VTP) therapy in men with low-risk prostate cancer. PATIENTS AND METHODS: In all, 42 men with low-risk prostate cancer were enrolled in the study but two who underwent anaesthesia for the procedure did not receive the drug or light dose. Thus, 40 men received a single dose of 2, 4 or 6 mg/kg WST11 activated by 200 J/cm light at 753 nm. WST11 was given as a 10-min intravenous infusion. The light dose was delivered using cylindrical diffusing fibres within hollow plastic needles positioned in the prostate using transrectal ultrasonography (TRUS) guidance and a brachytherapy template. Magnetic resonance imaging (MRI) was used to assess treatment effect at 7 days, with assessment of urinary function (International Prostate Symptom Score [IPSS]), sexual function (International Index of Erectile Function [IIEF]) and adverse events at 7 days, 1, 3 and 6 months after VTP. TRUS-guided biopsies were taken at 6 months. RESULTS: In all, 39 of the 40 treated men completed the follow-up. The Day-7 MRI showed maximal treatment effect (95% of the planned treatment volume) in men who had a WST11 dose of 4 mg/kg, light dose of 200 J/cm and light density index (LDI) of >1. In the 12 men treated with these parameters, the negative biopsy rate was 10/12 (83%) at 6 months, compared with 10/26 (45%) for the men who had either a different drug dose (10 men) or an LDI of <1 (16). Transient urinary symptoms were seen in most of the men, with no significant difference in IPSS score between baseline and 6 months after VTP. IIEF scores were not significantly different between baseline and 6 months after VTP. CONCLUSION: Treatment with 4 mg/kg TOOKAD Soluble activated by 753 nm light at a dose of 200 J/cm and an LDI of >1 resulted in treatment effect in 95% of the planned treatment volume and a negative biopsy rate at 6 months of 10/12 men (83%).

Laparoscopic radical prostatectomy for high-risk prostate cancer.

OBJECTIVE: To investigate the results of performing laparoscopic radical prostatectomy (LRP) in patients with high-risk prostate cancer (HRPC): PSA level of ≥20 ng/mL ± biopsy Gleason ≥8 ± clinical T stage ≥2c. PATIENTS AND METHODS: Of a total of 1975 patients having LRP during a 159-month period from 2000 to 2013, 446 (22.6%) had HRPC; all patients were staged by preoperative magnetic resonance imaging or computed tomography and isotope bone scanning. The median (range) patient age was 64.0 (36-79) years; body mass index 27.0 (18-43) kg/m(2) ; PSA level 8.1 (0.1-93) ng/mL and biopsy Gleason 8 (6-10). All patients had a pelvic lymphadenectomy, which was done using an extended template after April 2008 (53.3%). Neurovascular bundle (NVB) preservation was done in 41.5% (bilateral 26.3%; unilateral 15.2%) of patients; an incremental or partial nerve-sparing technique was used in 99 of the 302 (32.8%) NVBs preserved. RESULTS: The median (range) gland weight was 58.5 (20-161) g; operating time 180 (92-330) min; blood loss 200 (10-1400) mL; postoperative hospitalisation 3.0 (2-7) nights; catheterisation time 14 (2-35) days; complication rate 7.6%; lymph node (LN) count 16 (2-51); LN positivity 16.2%; LN involvement 2 (1-8); positive surgical margin (PSM) rate 26.0%; up-grading 2.5%; down-grading 4.3%; up-staging from T1/2 to T3, 24.7%; down-staging from T3 to T1/2, 6.1%. No cases were converted to open surgery and three patients were transfused (0.7%) after surgery. At a mean (range) follow-up of 24.9 (3-120) months, 79.2% of patients were free of biochemical recurrence, 91.8% were continent and 64.4% of previously potent non-diabetic men aged <70 years were potent after bilateral nerve preservation. CONCLUSION: The low morbidity, 55.4% specimen-confinement rate, 26.0% PSM rate, 79.2% biochemical disease-free survival, 91.8% continence rate and 64.4% potency rate, at 35.2 months in the present study serve as evidence firstly that surgery is an effective treatment for patients with HRPC, curing many and representing the first step of multi-modal treatment for others, and that LRP for HRPC appears to be as effective as open RP in this context.

Does prostate HistoScanning™ play a role in detecting prostate cancer in routine clinical practice? Results from three independent studies.

OBJECTIVES: To evaluate the ability of prostate HistoScanning™ (PHS; Advanced Medical Diagnostics, Waterloo, Belgium) to detect, characterize and locally stage prostate cancer, by comparing it with transrectal ultrasonography (TRUS)-guided prostate biopsies, transperineal template prostate biopsies (TTBs) and whole-mount radical prostatectomy specimens. SUBJECTS AND METHODS: Study 1. We recruited 24 patients awaiting standard 12-core TRUS-guided biopsies of the prostate to undergo PHS immediately beforehand. We compared PHS with the TRUS-guided biopsy results in terms of their ability to detect cancer within the whole prostate and to localize it to the correct side and to the correct region of the prostate. Lesions that were suspicious on PHS were biopsied separately. Study 2. We recruited 57 patients awaiting TTB to have PHS beforehand. We compared PHS with the TTB pathology results in terms of their ability to detect prostate cancer within the whole gland and to localize it to the correct side and to the correct sextant of the prostate. Study 3. We recruited 24 patients awaiting radical prostatectomy for localized prostate cancer to undergo preoperative PHS. We compared PHS with standardized pathological analysis of the whole-mount prostatectomy specimens in terms of their measurement of total tumour volume within the prostate, tumour volume within prostate sextants and volume of index lesions identified by PHS. RESULTS: The PHS-targeted biopsies had an overall cancer detection rate of 38.1%, compared with 62.5% with standard TRUS-guided biopsies. The sensitivity and specificity of PHS for localizing tumour to the correct prostate sextant, compared with standard TRUS-guided biopsies, were 100 and 5.9%, respectively. The PHS-targeted biopsies had an overall cancer detection rate of 13.4% compared with 54.4% for standard TTB. PHS had a sensitivity and specificity for cancer detection in the posterior gland of 100 and 13%, respectively, and for the anterior gland, 6 and 82%, respectively. We found no correlation between total tumour volume estimates from PHS and radical prostatectomy pathology (Pearson correlation coefficient -0.096). Sensitivity and specificity of PHS for detecting tumour foci ≥0.2 mL in volume were 63 and 53%. CONCLUSIONS: These three independent studies in 105 patients suggest that PHS does not reliably identify and characterize prostate cancer in the routine clinical setting.

The learning curve for laparoscopic extended pelvic lymphadenectomy for intermediate- and high-risk prostate cancer: implications for compliance with existing guidelines.

OBJECTIVE: To investigate the learning curve for performing extended pelvic lymphadenectomy (ePLND) during laparoscopic radical prostatectomy (LRP) in patients with intermediate- and high-risk prostate cancer. PATIENTS AND METHODS: In all, 500 patients underwent ePLND for intermediate- or high-risk prostate cancer by one surgeon during a 48-month period. A transperitoneal laparoscopic approach was used in all patients to allow adequate access to the internal iliac vessels. The variables chosen as being the most important discriminators of the quality of ePLND were operating time, complication rate and lymph node (LN) yield. The learning curves for ePLND were calculated using the cumulative sum and cumulative average methods and the number of procedures performed until attainment of acceptable failure rates (competence levels) was calculated. LN parameters were compared with the results from the preceding 311 cases where limited PLND was undertaken. RESULTS: The median (range) preoperative PSA level was 8.0(1-62.5) ng/mL and biopsy Gleason score was 7(6-10). In all, 64% of patients had intermediate-risk and 36% had high-risk prostate cancer. There were no intraoperative blood transfusions and no conversions to open surgery. The median (range) blood loss was 200(10-1400) mL and the postoperative transfusion rate was 1.6%. The operating time fell at a steady rate of 2.7% after the 15th case and plateaued after 130 patients. At competence levels of 5% and 10%, the learning curve for all complications ended after 346 and 136 patients, respectively. At a 5% competence level the learning curve for PLND-specific complications was 40 cases and there was no learning curve at a 10% competence level. The overall complication rate was 7.2% of which almost half (47%) were deemed to be PLND-specific. The cumulative average of the LN counts plateaued after 150 procedures. Furthermore, the median LN count after ePLND was more than double that of the authors' historical standard PLND controls (14 vs 6, P < 0.001) and increased with experience up to the end of the series (9 to 20). The likelihood of LN involvement (LNI) correlated with biopsy and pathological Gleason grade, clinical and pathological stage and d'Amico risk group. CONCLUSIONS: This study suggests a learning curve of ≈130 cases for operating time, 136 cases for all complications, 40 cases for PLND-specific complications and 150 cases for LN yield. The risk of LNI for patients with intermediate- and high-risk prostate cancer was 8.4% and 19.4%, respectively, which suggests that a significant proportion would benefit from ePLND. It also shows that ePLND can be safely incorporated into LRP, and therefore also into robot-assisted RP, in a high-volume setting.

The role of transperineal template prostate biopsies in restaging men with prostate cancer managed by active surveillance.

OBJECTIVE: To evaluate the role of transperineal template prostate biopsies in men on active surveillance. PATIENTS AND METHODS: In all, 101 men on active surveillance for prostate cancer underwent restaging transperineal template prostate biopsies at a single centre. Criteria for active surveillance were ≤75 years, Gleason ≤3+3, prostate-specific antigen (PSA) ≤15 ng/mL, clinical stage T1-2a and ≤50% ultrasound-guided transrectal biopsy cores positive for cancer with ≤10 mm of disease in a single core. The number of men with an increase in disease volume or Gleason grade on transperineal template biopsy and the number of men who later underwent radical treatment were assessed. The role of PSA and PSA kinetics were studied. RESULTS: In all, 34% of men had more significant prostate cancer on restaging transperineal template biopsies compared with their transrectal biopsies. Of these men, 44% had disease predominantly in the anterior part of the gland, an area often under-sampled by transrectal biopsies. In the group of men who had their restaging transperineal template biopsies within 6 months of commencing active surveillance 38% had more significant disease. There was no correlation with PSA velocity or PSA doubling time. In total, 33% of men stopped active surveillance and had radical treatment. CONCLUSIONS: Around one-third of men had more significant prostate cancer on transperineal template biopsies. This probably reflects under-sampling by initial transrectal biopsies rather than disease progression.

Laparoscopic cytoreductive nephrectomy: a three-center retrospective analysis.

INTRODUCTION: Metastatic renal cell carcinoma is associated with a poor prognosis. Given the current lack of effective systemic therapies and data suggesting a survival benefit from cytoreductive nephrectomy (CRN) before systemic therapy, we have retrospectively analyzed the experience of laparoscopic cytoreductive nephrectomy (LCRN) in three U.K. centers. The focus of this study was to assess the peri- and postoperative safety and hence feasibility of LCRN in the United Kingdom. PATIENTS AND METHODS: Twenty-five patients with metastatic renal cell carcinoma deemed suitable for systemic therapy underwent LCRN in three U.K. centers over a 4-year period. RESULTS: The tumors ranged from 3.4 cm in diameter to 12 cm. Operating times ranged from 89 (minimum) to 310 minutes (maximum), median 175 minutes. The median amount of blood loss was 150 mL, and hence the transfusion rate was low with only one patient requiring on-table transfusion and two patients requiring additional blood before discharge. Hospital stay ranged between 2.5 and 11 days; median postoperative stay was 3 days. CONCLUSIONS: In our initial experience, LCRN seems safe and feasible with low morbidity and a good perioperative outcome.