PI-QUAL version 2: an update of a standardised scoring system for the assessment of image quality of prostate MRI.

Multiparametric MRI is the optimal primary investigation when prostate cancer is suspected, and its ability to rule in and rule out clinically significant disease relies on high-quality anatomical and functional images. Avenues for achieving consistent high-quality acquisitions include meticulous patient preparation, scanner setup, optimised pulse sequences, personnel training, and artificial intelligence systems. The impact of these interventions on the final images needs to be quantified. The prostate imaging quality (PI-QUAL) scoring system was the first standardised quantification method that demonstrated the potential for clinical benefit by relating image quality to cancer detection ability by MRI. We present the updated version of PI-QUAL (PI-QUAL v2) which applies to prostate MRI performed with or without intravenous contrast medium using a simplified 3-point scale focused on critical technical and qualitative image parameters. CLINICAL RELEVANCE STATEMENT: High image quality is crucial for prostate MRI, and the updated version of the PI-QUAL score (PI-QUAL v2) aims to address the limitations of version 1. It is now applicable to both multiparametric MRI and MRI without intravenous contrast medium. KEY POINTS: High-quality images are essential for prostate cancer diagnosis and management using MRI. PI-QUAL v2 simplifies image assessment and expands its applicability to prostate MRI without contrast medium. PI-QUAL v2 focuses on critical technical and qualitative image parameters and emphasises T2-WI and DWI.

Clinical phenotypes and long-term outcome of kidney involvement in Erdheim-Chester histiocytosis.

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis that frequently infiltrates the peri-kidney space ("hairy kidney" appearance), kidney pelvis and proximal ureters, leading to obstructive uropathy. Here, we analyzed the clinical characteristics, imaging findings and long-term kidney outcome of a large multicenter cohort comprising 195 consecutive patients with ECD. Retroperitoneal peri-kidney or peri-ureteral involvement was detected at diagnosis in 147 patients. Of them, 70 had hydronephrosis (bilateral in 47), and 16 with kidney atrophy (unilateral in 14). Kidney vascular peduncle infiltration was found in 60 patients, and kidney artery stenosis in 31. The estimated glomerular filtration rate (eGFR) at diagnosis was significantly lower in patients with than in those without peri-kidney involvement (median 74 vs. 98 mL/min/1.73 m2). Ureteral stenting often failed to achieve kidney function recovery. A total of 181 patients received medical therapies: first-line treatments included interferon-α (61%), BRAF-inhibitors (17%), mTOR-inhibitors (7%), or other drugs (15%). These therapies were efficacious for ECD but rarely induced kidney function improvement (one-year eGFR increase over 25% in under 10% of patients). After a median of 43 months, 19% of patients died and 5% developed kidney failure. Among patients with peri-kidney involvement, 44% developed chronic kidney disease (CKD) 3-5 at five years vs. 5% of those without. Unadjusted predictors of advanced CKD and kidney failure/death were age over 50 years, hypertension, BRAFV600E mutation, and baseline eGFR. At multivariable analysis, cardiovascular comorbidities were associated with advanced CKD, and age over 50 years with kidney failure/death. Thus, kidney involvement is common in ECD and can lead to CKD or kidney failure despite effective medical therapies or urological procedures.

Clinical performance of magnetic resonance imaging and biomarkers for prostate cancer diagnosis in men at high genetic risk.

OBJECTIVES: To evaluate different scenarios for the management of early diagnosis of cancer (PCa) in men at high genetic risk, using recently developed blood and urinary molecular biomarkers in combination with clinical information alongside multiparametric magnetic resonance imaging (mpMRI). PATIENTS AND METHODS: A total of 322 patients with a high genetic risk (familial or personal history of cancers or a predisposing germline variant) were included in this study. The primary outcome was the detection rates of PCa (positive biopsy) or clinically significant PCa (biopsy with International Society of Urological Pathology [ISUP] grade >1). Clinical parameters included age, body mass index, ancestry, and germline mutational status, mpMRI, prostate-specific antigen density (PSAD), Prostate Health Index and urinary markers (Prostate Cancer Associated 3, SelectMdx™ and T2:ERG score) were assessed. Sensitivity (Se) and specificity (Sp) for each marker at their recommended cut-off for clinical practice were calculated. Comparison between diagnoses accuracy of each procedure and scenario was computed using mutual information based and direct effect contribution using a supervised Bayesian network approach. RESULTS: A mpMRI Prostate Imaging-Reporting and Data System (PI-RADS) score ≥3 showed higher Se than mpMRI PI-RADS score ≥4 for detection of PCa (82% vs 61%) and for the detection of ISUP grade >1 lesions (96% vs 80%). mpMRI PI-RADS score ≥3 performed better than a PSA level of ≥3 ng/mL (Se 96%, Sp 53% vs Se 91%, Sp 8%) for detection of clinically significant PCa. In case of negative mpMRI results, the supervised Bayesian network approach showed that urinary markers (with the same accuracy for all) and PSAD of ≥0.10 ng/mL/mL were the most useful indicators of decision to biopsy. CONCLUSIONS: We found that screening men at high genetic risk of PCa must be based on mpMRI without pre-screening based on a PSA level of >3 ng/mL, to avoid missing too many ISUP grade >1 tumours and to significantly reduce the number of unnecessary biopsies. However, urinary markers or a PSAD of ≥0.10 ng/mL/mL when mpMRI was negative increased the detection of ISUP grade >1 cancers. We suggest that a baseline mpMRI be discussed for men at high genetic risk from the age of 40 years.

Micro-ultrasound-guided biopsies versus systematic biopsies in the detection of prostate cancer: a systematic review and meta-analysis.

PURPOSE: The diagnosis of prostate cancer (PCa) still relies on the performance of both targeted (TB) and systematic biopsies (SB). Micro-ultrasound (mUS)-guided biopsies demonstrated a high sensitivity in detecting clinically significant prostate cancer (csPCa), which could be comparable to that of magnetic resonance imaging (MRI)-TB, but their added value has not been compared to SB yet. METHODS: We conducted a systematic review and meta-analysis, based on Medline, EMBASE, Scopus, and Web of Science, in accordance with PRISMA guidelines, to compare mUS-guided biopsies to SB. RESULTS: Based on the literature search of 2957 articles, 15 met the inclusion criteria (2967 patients). Most patients underwent mUS-guided biopsies, followed by MRI-TB and SB. Respectively 5 (n = 670) and 4 (n = 467) studies, providing raw data on SB, were included in a random-effect meta-analysis of the detection rate of csPCa, i.e. Gleason Grade Group (GGG) ≥ 2 or non-csPCa (GGG = 1). Overall, PCa was detected in 56-71% of men, with 31.3-49% having csPCa and 17-25.4% having non-csPCa. Regarding csPCa, mUS-guided biopsies identified 196 and SB 169 cases (Detection Ratio (DR): 1.18, 95% CI 0.83-1.68, I2 = 69%), favoring mUS-guided biopsies; regarding non-csPCa, mUS-guided biopsies identified 62 and SB 115 cases (DR: 0.55, 95% CI 0.41-0.73, I2 = 0%), also favoring mUS-guided biopsies by decreasing unnecessary diagnosis. CONCLUSION: Micro-ultrasound-guided biopsies compared favorably with SB for the detection of csPCa and detected fewer non-csPCa than SB. Prospective trials are awaited to confirm the interest of adding mUS-guided biopsies to MRI-TB to optimize csPCa detection without increasing overdiagnosis of non-csPCa.

What is the ideal combination therapy in de novo, oligometastatic, castration-sensitive prostate cancer?

PURPOSE: To review current evidence regarding the management of de novo, oligometastatic, castration-sensitive prostate cancer (PCa). METHODS: A literature search was conducted on PubMed/Medline and a narrative synthesis of the evidence was performed in August 2022. RESULTS: Oligometastatic disease is an intermediate state between localized and aggressive metastatic PCa defined by ≤ 3-5 metastatic lesions, although this definition remains controversial. Conventional imaging has limited accuracy in detecting metastatic lesions, and the implementation of molecular imaging could pave the way for a more personalized treatment strategy. However, oncological data supporting this strategy are needed. Radiotherapy to the primary tumor should be considered standard treatment for oligometastatic PCa (omPCa). However, it remains to be seen whether local therapy still has an additional survival benefit in patients with de novo omPCa when treated with the most modern systemic therapy combinations. There is insufficient evidence to recommend cytoreductive radical prostatectomy as local therapy; or stereotactic body radiotherapy as metastasis-directed therapy in patients with omPCa. Current data support the use of intensified systemic therapy with androgen deprivation therapy (ADT) and next-generation hormone therapies (NHT) for patients with de novo omPCa. Docetaxel has not demonstrated benefit in low volume disease. There are insufficient data to support the use of triple therapy (i.e., ADT + NHT + Docetaxel) in low volume disease. CONCLUSION: The present review discusses current data in de novo, omPCa regarding its definition, the increasing role of molecular imaging, the place of local and metastasis-directed therapies, and the intensification of systemic therapies.

Dynamic evaluation of MRI-targeted, systematic and combined biopsy for prostate cancer diagnosis through 10 years of practice in a single institution.

PURPOSE: To perform a dynamic evaluation of the prostate cancer (PCa) detection rate according to the biopsy strategy over 10 years of practice in a single institution that pioneered MRI-targeted fusion biopsy (MRI-TB). METHODS: This stage 4 IDEAL study prospectively included all consecutive patients who underwent transrectal prostate biopsy for clinically suspected PCa between January 2010 and November 2020. Patients with positive MRI (PIRADS score ≥ 3) underwent both MRI-TB and systematic biopsy (SB) while those with negative MRI (PIRADS score < 3) underwent SB only. The main outcome was the evolution of the detection rate of clinically relevant PCa (csPCa; grade ≥ 2). The secondary outcome was the change in PCa detection rate according to the biopsy method. RESULTS: A total of 2942 men underwent prostate MRI and a prostate biopsy: 2322 underwent MRI-TB and 620 had SB only. The detection rate of csPCa increased 2.5-fold from 23 to 58%. The detection rate of PCa and csPCa was significantly higher in patients who underwent MRI-TB compared to those who underwent SB only (67% vs. 52% and 40% vs. 32%, respectively (P < 0.001 for both comparisons)). The number of csPCa diagnosed by MRI-TB increased linearly over the study period and represented the majority of PCa diagnoses after 2016. CONCLUSION: Implementation of MRI-TB in patients with positive MRI led to improved detection of csPCa.

Heterogeneity of contemporary grade group 4 prostate cancer in radical prostatectomy specimens.

PURPOSE: The aim was to evaluate the prognostic role of sub-categories of ISUP 4 prostate cancer (PCa) on final pathology, and assess the tumor architecture prognostic role for predicting biochemical recurrence (BCR) after radical prostatectomy. METHODS: From a prospectively-maintained database, we included 370 individuals with ISUP 4 on final pathology. The main outcomes were to evaluate the relationship between different ISUP patterns within the group 4 with pathological and oncological outcomes. Binary logistic regression and Kaplan-Meier estimator were used to evaluate the role of the different categories (3 + 5, 4 + 4, 5 + 3) and tumor architecture (intraductal and/or cribriform) on pathological and oncological outcomes. RESULTS: Among the 370 individuals with ISUP considered for the study, 9, 85 and 6% had grade 3 + 5, 4 + 4 and 5 + 3 PCa, respectively. Overall, 74% had extracapsular extension, while lymph node invasion (LNI) was documented in 9%. A total of 144 patients experienced BCR during follow-up. After adjusting for PSA, pT, grade group, LNI and positive surgical margins (PSM), grade 3 + 5 was a protective factor (HR: 0.30, 95% CI: 0.13,0.68, p = 0.004) in predicting BCR relative to grade 4 + 4. Intraductal or cribriform architecture was correlated with BCR (HR: 5.99, 95% CI: 2.68, 13.4, p < 0.001) after adjusting for PSA, pT, grade group, LNI and PSM. CONCLUSIONS: Patients with tumor grade 3 + 5 had better pathological and prognostic outcomes compared to 4 + 4 or 5 + 3. When accounting for tumor architecture, the sub-stratification into subgroups lost its prognostic role and tumor architecture was the sole predictor of poorer prognosis in terms of biochemical recurrence.

Annual nationwide analysis of costs and post-operative outcomes after radical prostatectomy according to the surgical approach (open, laparoscopic, and robotic).

OBJECTIVE: Annual countrywide data are scarce when comparing surgical approaches in terms of hospital stay outcomes and costs for radical prostatectomy (RP). We aimed to assess the impact of surgical approach on post-operative outcomes and costs after RP by comparing open (ORP), laparoscopic (LRP), and robot-assisted (RARP) RP in the French healthcare system. PATIENTS AND METHODS: Data from all patients undergoing RP in France in 2020 were extracted from the central database of the national healthcare system. Primary endpoints were length of hospital stay (LOS including intensive care unit (ICU) stay if present), complications (estimated by severity index), hospital readmission rates (at 30 and 90 days), and direct costs of initial stay. RESULTS AND LIMITATIONS: A total of 19,018 RPs were performed consisting in ORP in 21.1%, LRP in 27.6%, and RARP in 51.3% of cases. RARP was associated with higher center volume (p < 0.001), lower complication rates (p < 0.001), shorter LOS (p < 0.001), and lower readmission rates (p = 0.004). RARP was associated with reduced direct stay costs (2286 euros) compared with ORP (4298 euros) and LRP (3101 euros). The main cost driver was length of stay. The main limitations were the lack of mid-term data, readmission details, and cost variations due to surgery system. CONCLUSIONS: This nationwide analysis demonstrates the benefits of RARP in terms of post-operative short-term outcomes. Higher costs related to the robotic system appear to be balanced by patient care improvements and reduced direct costs due to shorter LOS.

Prostate volume prediction on MRI: tools, accuracy and variability.

OBJECTIVE: A reliable estimation of prostate volume (PV) is essential to prostate cancer management. The objective of our multi-rater study was to compare intra- and inter-rater variability of PV from manual planimetry and ellipsoid formulas. METHODS: Forty treatment-naive patients who underwent prostate MRI were selected from a local database. PV and corresponding PSA density (PSAd) were estimated on 3D T2-weighted MRI (3 T) by 7 independent radiologists using the traditional ellipsoid formula (TEF), the newer biproximate ellipsoid formula (BPEF), and the manual planimetry method (MPM) used as ground truth. Intra- and inter-rater variability was calculated using the mixed model-based intraclass correlation coefficient (ICC). RESULTS: Mean volumes were 67.00 (± 36.61), 66.07 (± 35.03), and 64.77 (± 38.27) cm3 with the TEF, BPEF, and MPM methods, respectively. Both TEF and BPEF overestimated PV relative to MPM, with the former presenting significant differences (+ 1.91 cm3, IQ = [- 0.33 cm3, 5.07 cm3], p val = 0.03). Both intra- (ICC > 0.90) and inter-rater (ICC > 0.90) reproducibility were excellent. MPM had the highest inter-rater reproducibility (ICC = 0.999). Inter-rater PV variation led to discrepancies in classification according to the clinical criterion of PSAd > 0.15 ng/mL for 2 patients (5%), 7 patients (17.5%), and 9 patients (22.5%) when using MPM, TEF, and BPEF, respectively. CONCLUSION: PV measurements using ellipsoid formulas and MPM are highly reproducible. MPM is a robust method for PV assessment and PSAd calculation, with the lowest variability. TEF showed a high degree of concordance with MPM but a slight overestimation of PV. Precise anatomic landmarks as defined with the BPEF led to a more accurate PV estimation, but also to a higher variability. KEY POINTS: • Manual planimetry used for prostate volume estimation is robust and reproducible, with the lowest variability between readers. • Ellipsoid formulas are accurate and reproducible but with higher variability between readers. • The traditional ellipsoid formula tends to overestimate prostate volume.

[Penile carcinoma: Practical issues, from the biopsy to surgery]. / Cancer du pénis : problèmes pratiques du quotidien, de la biopsie à la chirurgie.

The management of a penile carcinoma is complex, a collaboration between radiologist, pathologist and urologist is necessary to obtain a correct staging. In this review we try to demonstrate step by step how to achieve a complete pathology report, how to manage the patient (imaging, biopsy, fresh frozen section and surgery).

Limiting radiation exposure during prostatic arteries embolization: influence of patient characteristics, anatomical conditions, and technical factors.

OBJECTIVE: To assess the influence of patient characteristics, anatomical conditions, and technical factors on radiation exposure during prostatic arteries embolization (PAE) performed for benign prostatic hyperplasia. MATERIALS AND METHODS: Patient characteristics (age, body mass index (BMI)), anatomical conditions (number of prostatic arteries, anastomosis), and technical factors (use of cone beam computed tomography (CBCT), large display monitor (LDM), and magnification) were recorded as well as total air kerma (AK), dose area product (DAP), fluoroscopy time (FT), and number of acquisitions (NAcq). Associations between potential dose-influencing factors and AK using univariate analysis and a multiple linear regression model were assessed. RESULTS: Forty-one consecutive men (68 ± 8 years, min-max: 40-76) were included. LDM and CBCT decreased the use of small field of view with 13.9 and 3.8% respectively, both p < 0.001. The use of a LDM significantly reduced AK (1006.6 ± 471.7 vs. 1412 ± 754.6 mGy, p = 0.02), DAP (119.4 ± 64.4 vs. 167.9 ± 99.2, p = 0.04), FT (40.4 ± 11.5 vs. 53.6 ± 25.5 min, p = 0.01), and NAcq (16.3 ± 6.3 vs. 18.2 ± 7, p = 0.04). In multivariate analysis, AK reduction was associated with lower patient BMI (ß = 0.359, p = 0.002), shorter FT (ß = 0.664, p < 0.001) and CBCT use (ß = - 0.223, p = 0.03), and decreased NAcq (ß = 0.229, p = 0.04). CONCLUSION: LDM and CBCT are important technical dose-related factors to help reduce radiation exposure during PAE, and should be considered in standard practice. KEY POINTS: • The use of large display monitor (LDM) and cone beam computed tomography (CBCT) both decreased the need for magnification during prostatic arteries embolization (PAE). • The use of LDM reduces radiation exposure during PAE. • Total air kerma is associated with patient's body mass index, fluoroscopy time, CBCT, and the number of acquisitions.

PI-RADS Version 2.1: A Critical Review, From the AJR Special Series on Radiology Reporting and Data Systems.

PI-RADS version 2.1 updates the technical parameters for multiparametric MRI (mpMRI) of the prostate and revises the imaging interpretation criteria while maintaining the framework introduced in version 2. These changes have been considered an improvement, although some issues remain unresolved, and new issues have emerged. Areas for improvement discussed in this review include the need for more detailed mpMRI protocols with optimization for 1.5-T and 3-T systems; lack of validation of revised transition zone interpretation criteria and need for clarifications of the revised DWI and dynamic contrast-enhanced imaging criteria and central zone (CZ) assessment; the need for systematic evaluation and reporting of background changes in signal intensity in the prostate that can negatively affect cancer detection; creation of a new category for lesions that do not fit into the PI-RADS assessment categories (i.e., PI-RADS M category); inclusion of quantitative parameters beyond size to evaluate lesion aggressiveness; adjustments to the structured report template, including standardized assessment of the risk of extraprostatic extension; development of parameters for image quality and performance control; and suggestions for expansion of the system to other indications (e.g., active surveillance and recurrence).

Diagnosis of prostate cancer in one day: The benefits of cytology in tumour detection.

OBJECTIVE: Prostate cancer (PCa) is a frequent and mortal disease. The aim of this study was to introduce a "diagnosis and handling of PCa in one day" concept, accelerating the handling of PCa patients by giving diagnostic results within 3 hours with the help of prostate cytology. Standard histology served as the control. MATERIAL AND METHODS: After multiparametric MRI, prostate biopsies were taken and one was used for imprint cytology on superfrost slides. The cytology samples were stained by p63/p504s double staining, a standard stain in PCa histology, followed by on-site interpretation. RESULTS: Among 129 patients, 39.5% had a prior history of PCa and were either under active surveillance or had been treated by focal therapy. The others came with suspicion of PCa. In 80.8% of the cases, the cytology and histology results agreed. In low-grade PCa the detection with cytology was more difficult with 72.4% agreement, whereas for intermediate and high-grade PCa the concordance with histology was 81.8 and 90%, respectively. False positive cases were less than 4.0%. CONCLUSION: Cytology of the prostate is unusual, but our study is the first to show it is feasible and gives immediate results that are satisfactory, especially in more aggressive cases. Immunocytology can be easily integrated into the laboratory. Our technique allows quicker handling of PCa, which can soften the psychological impact on men waiting for the diagnosis of PCa.

Imaging protocols for CT urography: results of a consensus conference from the French Society of Genitourinary Imaging.

OBJECTIVES: To develop technical guidelines for computed tomography urography. METHODS: The French Society of Genitourinary Imaging organised a Delphi consensus conference with a two-round Delphi survey followed by a face-to-face meeting. Consensus was strictly defined using a priori criteria. RESULTS: Forty-two expert uro-radiologists completed both survey rounds with no attrition between the rounds. Ninety-six (70%) of the initial 138 statements of the questionnaire achieved final consensus. An intravenous injection of 20 mg of furosemide before iodinated contrast medium injection was judged mandatory. Improving the quality of excretory phase imaging through oral or intravenous hydration of the patient or through the use of an abdominal compression device was not deemed necessary. The patient should be imaged in the supine position and placed in the prone position only at the radiologist's request. The choice between single-bolus and split-bolus protocols depends on the context, but split-bolus protocols should be favoured whenever possible to decrease patient irradiation. Repeated single-slice test acquisitions should not be performed to decide of the timing of excretory phase imaging; instead, excretory phase imaging should be performed 7 min after the injection of the contrast medium. The optimal combination of unenhanced, corticomedullary phase and nephrographic phase imaging depends on the context; suggestions of protocols are provided for eight different clinical situations. CONCLUSION: This expert-based consensus conference provides recommendations to standardise the imaging protocol for computed tomography urography. KEY POINTS: • To improve excretory phase imaging, an intravenous injection of furosemide should be performed before the injection of iodinated contrast medium. • Systematic oral or intravenous hydration is not necessary to improve excretory phase imaging. • The choice between single-bolus and split-bolus protocols depends on the context, but split-bolus protocols should be favoured whenever possible to decrease patient irradiation.

Imaging protocols for renal multiparametric MRI and MR urography: results of a consensus conference from the French Society of Genitourinary Imaging.

OBJECTIVES: To develop technical guidelines for magnetic resonance imaging aimed at characterising renal masses (multiparametric magnetic resonance imaging, mpMRI) and at imaging the bladder and upper urinary tract (magnetic resonance urography, MRU). METHODS: The French Society of Genitourinary Imaging organised a Delphi consensus conference with a two-round Delphi survey followed by a face-to-face meeting. Two separate questionnaires were issued for renal mpMRI and for MRU. Consensus was strictly defined using a priori criteria. RESULTS: Forty-two expert uroradiologists completed both survey rounds with no attrition between the rounds. Fifty-six of 84 (67%) statements of the mpMRI questionnaire and 44/71 (62%) statements of the MRU questionnaire reached final consensus. For mpMRI, there was consensus that no injection of furosemide was needed and that the imaging protocol should include T2-weighted imaging, dual chemical shift imaging, diffusion-weighted imaging (use of multiple b-values; maximal b-value, 1000 s/mm2) and fat-saturated single-bolus multiphase (unenhanced, corticomedullary, nephrographic) contrast-enhanced imaging; late imaging (more than 10 min after injection) was judged optional. For MRU, the patients should void their bladder before the examination. The protocol must include T2-weighted imaging, anatomical fast T1/T2-weighted imaging, diffusion-weighted imaging (use of multiple b-values; maximal b-value, 1000 s/mm2) and fat-saturated single-bolus multiphase (unenhanced, corticomedullary, nephrographic, excretory) contrast-enhanced imaging. An intravenous injection of furosemide is mandatory before the injection of contrast medium. Heavily T2-weighted cholangiopancreatography-like imaging was judged optional. CONCLUSION: This expert-based consensus conference provides recommendations to standardise magnetic resonance imaging of kidneys, ureter and bladder. KEY POINTS: • Multiparametric magnetic resonance imaging (mpMRI) aims at characterising renal masses; magnetic resonance urography (MRU) aims at imaging the urinary bladder and the collecting systems. • For mpMRI, no injection of furosemide is needed. • For MRU, an intravenous injection of furosemide is mandatory before the injection of contrast medium; heavily T2-weighted cholangiopancreatography-like imaging is optional.

Use of prostate systematic and targeted biopsy on the basis of multiparametric MRI in biopsy-naive patients (MRI-FIRST): a prospective, multicentre, paired diagnostic study.

BACKGROUND: Whether multiparametric MRI improves the detection of clinically significant prostate cancer and avoids the need for systematic biopsy in biopsy-naive patients remains controversial. We aimed to investigate whether using this approach before biopsy would improve detection of clinically significant prostate cancer in biopsy-naive patients. METHODS: In this prospective, multicentre, paired diagnostic study, done at 16 centres in France, we enrolled patients aged 18-75 years with prostate-specific antigen concentrations of 20 ng/mL or less, and with stage T2c or lower prostate cancer. Eligible patients had been referred for prostate multiparametric MRI before a first set of prostate biopsies, with a planned interval of less than 3 months between MRI and biopsies. An operator masked to multiparametric MRI results did a systematic biopsy by obtaining 12 systematic cores and up to two cores targeting hypoechoic lesions. In the same patient, another operator targeted up to two lesions seen on MRI with a Likert score of 3 or higher (three cores per lesion) using targeted biopsy based on multiparametric MRI findings. Patients with negative multiparametric MRI (Likert score ≤2) had systematic biopsy only. The primary outcome was the detection of clinically significant prostate cancer of International Society of Urological Pathology grade group 2 or higher (csPCa-A), analysed in all patients who received both systematic and targeted biopsies and whose results from both were available for pathological central review, including patients who had protocol deviations. This study is registered with ClinicalTrials.gov, number NCT02485379, and is closed to new participants. FINDINGS: Between July 15, 2015, and Aug 11, 2016, we enrolled 275 patients. 24 (9%) were excluded from the analysis. 53 (21%) of 251 analysed patients had negative (Likert ≤2) multiparametric MRI. csPCa-A was detected in 94 (37%) of 251 patients. 13 (14%) of these 94 patients were diagnosed by systematic biopsy only, 19 (20%) by targeted biopsy only, and 62 (66%) by both techniques. Detection of csPCa-A by systematic biopsy (29·9%, 95% CI 24·3-36·0) and targeted biopsy (32·3%, 26·5-38·4) did not differ significantly (p=0·38). csPCa-A would have been missed in 5·2% (95% CI 2·8-8·7) of patients had systematic biopsy not been done, and in 7·6% (4·6-11·6) of patients had targeted biopsy not been done. Four grade 3 post-biopsy adverse events were reported (3 cases of prostatitis, and 1 case of urinary retention with haematuria). INTERPRETATION: There was no difference between systematic biopsy and targeted biopsy in the detection of ISUP grade group 2 or higher prostate cancer; however, this detection was improved by combining both techniques and both techniques showed substantial added value. Thus, obtaining a multiparametric MRI before biopsy in biopsy-naive patients can improve the detection of clinically significant prostate cancer but does not seem to avoid the need for systematic biopsy. FUNDING: French National Cancer Institute.

Update on the ICUD-SIU consultation on multi-parametric magnetic resonance imaging in localised prostate cancer.

INTRODUCTION: Prostate cancer (PCa) imaging is a rapidly evolving field. Dramatic improvements in prostate MRI during the last decade will probably change the accuracy of diagnosis. This chapter reviews recent current evidence about MRI diagnostic performance and impact on PCa management. MATERIALS AND METHODS: The International Consultation on Urological Diseases nominated a committee to review the literature on prostate MRI. A search of the PubMed database was conducted to identify articles focussed on MP-MRI detection and staging protocols, reporting and scoring systems, the role of MP-MRI in diagnosing PCa prior to biopsy, in active surveillance, in focal therapy and in detecting local recurrence after treatment. RESULTS: Differences in opinion were reported in the use of the strength of magnets [1.5 Tesla (T) vs. 3T] and coils. More agreement was found regarding the choice of pulse sequences; diffusion-weighted MRI (DW-MRI), dynamic contrast-enhanced MRI (DCE MRI), and/or MR spectroscopy imaging (MRSI) are recommended in addition to conventional T2-weighted anatomical sequences. In 2015, the Prostate Imaging Reporting and Data System (PI-RADS version 2) was described to standardize image acquisition and interpretation. MP-MRI improves detection of clinically significant PCa (csPCa) in the repeat biopsy setting or before the confirmatory biopsy in patients considering active surveillance. It is useful to guide focal treatment and to detect local recurrences after treatment. Its role in biopsy-naive patients or during the course of active surveillance remains debated. CONCLUSION: MP-MRI is increasingly used to improve detection of csPCa and for the selection of a suitable therapeutic approach.

MRI for prostate cancer: can computed high b-value DWI replace native acquisitions?

OBJECTIVE: To compare computed high b-value diffusion-weighted images (c-DWI) derived from low b-value DWI images and acquired high b-value DWI (a-DWI), in overall image quality and prostate cancer detection rate. MATERIALS AND METHODS: A total of 124 consecutive men with suspected prostate cancer (PCa) underwent diagnosis prostate MRI on a 3.0 T MR system using a 32-channel phased-array torso coil. Among them, 63 underwent prostate biopsy. MRI protocol included 3DT2w images, high resolution Fov Optimized and Constrained Undistorted Single-Shot (FOCUS™) DWI images with b-values of 100, 400, 800, and 2000 s/mm2 and dynamic contrast enhanced images. C-DWI images (2000 and 2500 s/mm2) were derived from the three lower acquired b-value DWI images using a mono-exponential diffusion decay. C-DWI and acquired high b-value DWI (a-DWI) (2000 s/mm2) were compared for image quality (background signal suppression, anatomic clarity, ghosting, distortion) and tumor conspicuity by four radiologists. RESULTS: C-DWIs demonstrated higher rating than a-DWIs for overall image quality despite worsened ghosting. In patients with a biopsy, similar detection rate was observed while conspicuity was better with c-DWI (p < 0.001). Non-acquisition of high b-value a-DWI reduced total acquisition time by 220 s per patient. CONCLUSION: C-DWI provides a substantial reduction in acquisition time while maintaining comparable prostate cancer detection rate and improving global image quality. KEY POINTS: • Computed DWI improves global quality of prostate MRI. • Computed DWI improves analysis of DWI images with decrease acquisition time. • Computed DWI provides greater background suppression of parenchyma and improves conspicuity of suspicious lesion.

Dynamic contrast-enhanced imaging in localizing local recurrence of prostate cancer after radiotherapy: Limited added value for readers of varying level of experience.

BACKGROUND: The incremental value of dynamic contrast-enhanced (DCE) imaging in localizing radiorecurrent prostate cancer is uncertain. PURPOSE: To assess the added-value of DCE imaging to the combination T2 -weighted imaging (T2 W)+diffusion-weighted imaging (DWI) in detecting locally radiorecurrent prostate cancer (PCa), by radiologists with different levels of experience. STUDY TYPE: Analytic retrospective study. POPULATION: In all, 52 men with biological suspected PCa recurrence after radiotherapy were retrospectively included. FIELD STRENGTH/SEQUENCE: All men underwent prostatic MRI (1.5T or 3T), including T2 W, DWI, and DCE imagings, before biopsies. ASSESSMENT: Two junior (6 months' experience) and two senior readers (more than 3 years' experience) independently assigned a Likert score for each prostatic sextant on T2 W+DW+DCE imagings, then on T2 W+DW imagings, 4 weeks later. STATISTICAL TESTS: The reference standard was prostatic biopsies. For two levels of positivity of Likert score, 3/5 and 4/5, sensitivity, specificity, area under the receiver operating curve (AUC), and interreader agreement were compared. RESULTS: T2 W+DWI+DCE and T2 W+DWI imaging had similar AUC at lobe and sextant level (0.853-0.946 vs. 0.819-0.955, P from 0.071-0.534). Using a Likert score ≥4/5, T2 W+DWI+DCE significantly improved the sensitivity for junior readers at the patient, lobe, and sextant level (40-80% vs. 22-66%, P < 0.0001-0.041). Sensitivity was not significantly modified with DCE imaging for senior readers (54-95% vs. 50-91%, P from 0.074-1). Specificity was not modified for all readers (50-100% vs. 50%-100%, P from 0.134-1). DCE imaging improved interreader agreement for a Likert score ≥4/5 (kappa from 0.6-0.73 vs. 0.38-0.73). DATA CONCLUSION: The addition of DCE imaging did not significantly improve accuracy in recurrent PCa detection after radiotherapy, whatever the level of experience of the readers. However, the addition of DCE imaging slightly improved the sensitivity for less-experienced readers and increased their diagnostic confidence. LEVEL OF EVIDENCE: 3 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;48:1012-1023.

Editorial Comment: Advances in MRI and PET of the prostate: concurrence or complementarity?

This Editorial Comment refers to the articles "Diagnostic evaluation of magnetization transfer and diffusion kurtosis imaging for prostate cancer detection in a re-biopsy population" by Barrett T et al., Eur Radiol. 2017 Dec 8 and "18F-Fluciclovine PET/MRI for preoperative lymph node staging in high-risk prostate cancer patients" by Selnæs KM et al., Eur Radiol. 2018 Jan 2.