Prostagram magnetic resonance imaging in a screening population: Prostate Imaging-Reporting and Data System or Likert?

OBJECTIVE: To compare biopsy recommendation rates and accuracy of the Prostate Imaging-Reporting and Data System, version 2 (PI-RADSv2) with the Likert scale for detection of clinically significant and insignificant prostate cancer in men screened within the Imperial Prostate 1 Prostate Cancer Screening Trial Using Imaging (IP1-PROSTAGRAM). PATIENTS AND METHODS: Men aged 50-69 years were screened with Prostagram MRI. Scans were prospectively reported using both PI-RADSv2 (excluding dynamic contrast-enhanced sequence score) and 5-point Likert scores by expert uro-radiologists. Systematic and targeted transperineal biopsy was recommended if the scan was scored ≥ 3, based on either reporting system. The proportion of patients recommended for biopsy and detection rates for Grade Groups (GGs) 1 and ≥ 2 were compared. Receiver operating characteristic (ROC) analysis was performed to compare performance. RESULTS: A total of 406 men underwent Prostagram MRI. The median (interquartile range) age and prostate-specific antigen level were 57 (53-61) years and 0.91 (0.56-1.74) ng/mL, respectively. At MRI score ≥ 3, more patients were recommended for biopsy based on Likert criteria (94/406; 23%, 95% confidence interval [CI] 19.2%-27.6%) compared to PI-RADSv2 (72/406; 18%, 95% CI 14.2%-21.9%; P = 0.03). For MRI scores ≥ 4, PI-RADSv2 and Likert scales led to 43/406 (11%, 95% CI 7.9%-14.1%) and 35/406 (9%, 95% CI 6.2%-11.9%) men recommended for biopsy (P = 0.40). For GG ≥ 2 detection, PIRADSv2 and Likert detected 22% (95% CI 11.4%-30.8%, 14/72) and 16% (95% CI 9.5%-25.3%, 15/94), respectively (P = 0.56). For GG1 cancers detection these were 11% (95% CI 4.3%-19.6%, seven of 72) vs 11% (95% CI 4.7%-17.8%, nine of 94; P = 1.00). The accuracy of PI-RADSv2 and Likert scale was similar (area under the ROC curve 0.64 vs 0.65, P = 0.95). CONCLUSIONS: In reporting non-contrast-enhanced Prostagram MRI in a screening population, the PI-RADSv2 and Likert scoring systems were equally accurate; however, Likert scale use led to more men undergoing biopsy without a subsequent increase in significant cancer detection rates. To improve reporting of Prostagram MRI, either the PI-RADSv2 or a modified Likert scale or a standalone scoring system should be developed.

Experiences of 'traditional' and 'one-stop' MRI-based prostate cancer diagnostic pathways in England: a qualitative study with patients and GPs.

OBJECTIVES: This study aimed to understand and explore patient and general practitioner (GP) experiences of 'traditional' and 'one-stop' prostate cancer diagnostic pathways in England. DESIGN: Qualitative study using semi-structured interviews, analysed using inductive thematic analysis SETTING: Patients were recruited from National Health Service (NHS) Trusts in London and in Devon; GPs were recruited via National Institute for Health Research (NIHR) Clinical Research Networks. Interviews were conducted in person or via telephone. PARTICIPANTS: Patients who had undergone a MRI scan of the prostate as part of their diagnostic work-up for possible prostate cancer, and GPs who had referred at least one patient for possible prostate cancer in the preceding 12 months. RESULTS: 22 patients (aged 47-80 years) and 10 GPs (6 female, aged 38-58 years) were interviewed. Patients described three key themes: cancer beliefs in relation to patient's attitudes towards prostate cancer;communication with their GP and specialist having a significant impact on experience of the pathway and pathway experience being influenced by appointment and test burden. GP interview themes included: the challenges of dealing with imperfect information in the current pathway; managing uncertainty in identifying patients with possible prostate cancer and sharing this uncertainty with them, and other social, cultural and personal contextual influences. CONCLUSIONS: Patients and GPs reported a range of experiences and views of the current prostate cancer diagnostic pathways in England. Patients valued 'one-stop' pathways integrating prostate MRI and diagnostic consultations with specialists over the more traditional approach of several hospital appointments. GPs remain uncertain how best to identify patients needing referral for urgent prostate cancer testing due to the lack of accurate triage and risk assessment strategies.

Metastatic prostate cancer men's attitudes towards treatment of the local tumour and metastasis evaluative research (IP5-MATTER): protocol for a prospective, multicentre discrete choice experiment study.

INTRODUCTION: Systemic therapy with androgen deprivation therapy (ADT) and intensification with agents such as docetaxel, abiraterone acetate and enzalutamide has resulted in improved overall survival in men with de novo synchronous metastatic hormone-sensitive prostate cancer (mHSPC). Novel local cytoreductive treatments and metastasis-directed therapy are now being evaluated. Such interventions may provide added survival benefit or delay the requirement for further systemic agents and associated toxicity but can confer additional harm. Understanding men's preferences for treatment options in this disease state is crucial for patients, clinicians, carers and future healthcare service providers. METHODS: Using a prospective, multicentre discrete choice experiment (DCE), we aim to determine the attributes associated with treatment that are most important to men with mHSPC. Furthermore, we plan to determine men's preferences for, and trade-offs between, the attributes (survival and side effects) of different treatment options including systemic therapy, local cytoreductive approaches (external beam radiotherapy, cytoreductive radical prostatectomy or minimally invasive ablative therapy) and metastases-directed therapies (metastasectomy or stereotactic ablative body radiotherapy). All men with newly diagnosed mHSPC within 4 months of commencing ADT and WHO performance status 0-2 are eligible. Men who have previously consented to a cytoreductive treatment or have developed castrate-resistant disease will be excluded. This study includes a qualitative analysis component, with patients (n=15) and healthcare professionals (n=5), to identify and define the key attributes associated with treatment options that would warrant trade-off evaluation in a DCE. The main phase component planned recruitment is 300 patients over 1 year, commencing in January 2021, with planned study completion in March 2022. ETHICS AND DISSEMINATION: Ethical approval was obtained from the Health Research Authority East of England, Cambridgeshire and Hertfordshire Research Ethics Committee (Reference: 20/EE/0194). Project information will be reported on the publicly available Imperial College London website and the Heath Economics Research Unit (HERU website including the HERU Blog). We will use the social media accounts of IP5-MATTER, Imperial Prostate London, HERU and the individual researchers to disseminate key findings following publication. Findings from the study will be presented at national/international conferences and peer-reviewed journals. Authorship policy will follow the recommendations of the International Committee of Medical Journal Editors. TRIAL REGISTRATION NUMBER: NCT04590976.

Additional Treatments to the Local tumour for metastatic prostate cancer-Assessment of Novel Treatment Algorithms (IP2-ATLANTA): protocol for a multicentre, phase II randomised controlled trial.

INTRODUCTION: Survival in men diagnosed with de novo synchronous metastatic prostate cancer has increased following the use of upfront systemic treatment, using chemotherapy and other novel androgen receptor targeted agents, in addition to standard androgen deprivation therapy (ADT). Local cytoreductive and metastasis-directed interventions are hypothesised to confer additional survival benefit. In this setting, IP2-ATLANTA will explore progression-free survival (PFS) outcomes with the addition of sequential multimodal local and metastasis-directed treatments compared with standard care alone. METHODS: A phase II, prospective, multicentre, three-arm randomised controlled trial incorporating an embedded feasibility pilot. All men with new histologically diagnosed, hormone-sensitive, metastatic prostate cancer, within 4 months of commencing ADT and of performance status 0 to 2 are eligible. Patients will be randomised to Control (standard of care (SOC)) OR Intervention 1 (minimally invasive ablative therapy to prostate±pelvic lymph node dissection (PLND)) OR Intervention 2 (cytoreductive radical prostatectomy±PLND OR prostate radiotherapy±pelvic lymph node radiotherapy (PLNRT)). Metastatic burden will be prespecified using the Chemohormonal Therapy Versus Androgen Ablation Randomized Trial for Extensive Disease (CHAARTED) definition. Men with low burden disease in intervention arms are eligible for metastasis-directed therapy, in the form of stereotactic ablative body radiotherapy (SABR) or surgery. Standard systemic therapy will be administered in all arms with ADT±upfront systemic chemotherapy or androgen receptor agents. Patients will be followed-up for a minimum of 2 years. PRIMARY OUTCOME: PFS. Secondary outcomes include predictive factors for PFS and overall survival; urinary, sexual and rectal side effects. Embedded feasibility sample size is 80, with 918 patients required in the main phase II component. Study recruitment commenced in April 2019, with planned follow-up completed by April 2024. ETHICS AND DISSEMINATION: Approved by the Health Research Authority (HRA) Research Ethics Committee Wales-5 (19/WA0005). Study results will be submitted for publication in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT03763253; ISCRTN58401737.

Understanding virtual urology clinics: a systematic review.

OBJECTIVES: To perform a systematic review to identify the clinical, fiscal and environmental evidence on the use of urological telehealth and/or virtual clinic (VC) strategies, and to highlight research gaps in this rapidly evolving field. METHODS: Our PROSPERO-registered (CRD42019151946) systematic search of Embase, Medline and the Cochrane Review Database was performed to identify original research articles pertaining to adult urology telehealth or VC strategies. Risk-of-bias (RoB) assessment was performed according to the Cochrane 2.0 RoB tool or the Joanna Briggs Institute Checklist for non-randomized studies. RESULTS: A total of 5813 participants were included from 18 original articles (two randomized controlled trials [RCTs], 10 prospective studies, six retrospective studies). Urology sub-specialities comprised: uro-oncology (n = 6); general urology (n = 8); endo-urology (n = 2); and lower urinary tract symptoms and/or incontinence (n = 2). Across all sub-specialties, prospective studies using VCs reported a primary median (interquartile range [IQR]) VC discharge rate of 16.6 (14.7-29.8)% and a primary median (IQR) face-to-face (FTF) clinic referral rate of 32.4 (15.5-53.3)%. Direct cost analysis demonstrated median (IQR) annual cost savings of £56 232 (£46 260-£61 116). Grade II and IIIb complications were reported in two acute ureteric colic studies, with rates of 0.20% (3/1534) and 0.13% (2/1534), respectively. The annual carbon footprint avoided ranged from 0.7 to 4.35 metric tonnes of CO2 emissions, depending on the mode of transport used. Patient satisfaction was inconsistently reported, and assessments lacked prospective evaluation using validated questionnaires. CONCLUSION: Urology VCs are a promising new platform which can offer clinical, financial and environmental benefits to support an increasing urological referral burden. Further prospective evidence is required across urological sub-specialties to confirm equivalency and safety against traditional FTF assessment.

Localising occult prostate cancer metastasis with advanced imaging techniques (LOCATE trial): a prospective cohort, observational diagnostic accuracy trial investigating whole-body magnetic resonance imaging in radio-recurrent prostate cancer.

BACKGROUND: Accurate whole-body staging following biochemical relapse in prostate cancer is vital in determining the optimum disease management. Current imaging guidelines recommend various imaging platforms such as computed tomography (CT), Technetium 99 m (99mTc) bone scan and 18F-choline and recently 68Ga-PSMA positron emission tomography (PET) for the evaluation of the extent of disease. Such approach requires multiple hospital attendances and can be time and resource intensive. Recently, whole-body magnetic resonance imaging (WB-MRI) has been used in a single visit scanning session for several malignancies, including prostate cancer, with promising results, providing similar accuracy compared to the combined conventional imaging techniques. The LOCATE trial aims to investigate the application of WB-MRI for re-staging of patients with biochemical relapse (BCR) following external beam radiotherapy and brachytherapy in patients with prostate cancer. METHODS/DESIGN: The LOCATE trial is a prospective cohort, multi-centre, non-randomised, diagnostic accuracy study comparing WB-MRI and conventional imaging. Eligible patients will undergo WB-MRI in addition to conventional imaging investigations at the time of BCR and will be asked to attend a second WB-MRI exam, 12-months following the initial scan. WB-MRI results will be compared to an enhanced reference standard comprising all the initial, follow-up imaging and non-imaging investigations. The diagnostic performance (sensitivity and specificity analysis) of WB-MRI for re-staging of BCR will be investigated against the enhanced reference standard on a per-patient basis. An economic analysis of WB-MRI compared to conventional imaging pathways will be performed to inform the cost-effectiveness of the WB-MRI imaging pathway. Additionally, an exploratory sub-study will be performed on blood samples and exosome-derived human epidermal growth factor receptor (HER) dimer measurements will be taken to investigate its significance in this cohort. DISCUSSION: The LOCATE trial will compare WB-MRI versus the conventional imaging pathway including its cost-effectiveness, therefore informing the most accurate and efficient imaging pathway. TRIAL REGISTRATION: LOCATE trial was registered on ClinicalTrial.gov on 18th of October 2016 with registration reference number NCT02935816.

Multiparametric whole-body 3.0-T MRI in newly diagnosed intermediate- and high-risk prostate cancer: diagnostic accuracy and interobserver agreement for nodal and metastatic staging.

OBJECTIVES: To determine the diagnostic accuracy and interobserver concordance of whole-body (WB)-MRI, vs. 99mTc bone scintigraphy (BS) and 18fluoro-ethyl-choline (18F-choline) PET/CT for the primary staging of intermediate/high-risk prostate cancer. METHODS: An institutional review board approved prospective cohort study carried out between July 2012 and November 2015, whereby 56 men prospectively underwent 3.0-T multiparametric (mp)-WB-MRI in addition to BS (all patients) ± 18F-choline PET/CT (33 patients). MRI comprised pre- and post-contrast modified Dixon (mDixon), T2-weighted (T2W) imaging, and diffusion-weighted imaging (DWI). Patients underwent follow-up mp-WB-MRI at 1 year to derive the reference standard. WB-MRIs were reviewed by two radiologists applying a 6-point scale and a locked sequential read (LSR) paradigm for the suspicion of nodal (N) and metastatic disease (M1a and M1b). RESULTS: The mean sensitivity/specificity of WB-MRI for N1 disease was 1.00/0.96 respectively, compared with 1.00/0.82 for 18F-choline PET/CT. The mean sensitivity and specificity of WB-MRI, 18F-choline PET/CT, and BS were 0.90/0.88, 0.80/0.92, and 0.60/1.00 for M1b disease. ROC-AUC did not show statistically significant improvement for each component of the LSR; mean ROC-AUC 0.92, 0.94, and 0.93 (p < 0.05) for mDixon + DWI, + T2WI, and + contrast respectively. WB-MRI had an interobserver concordance (κ) of 0.79, 0.68, and 0.58 for N1, M1a, and M1b diseases respectively. CONCLUSIONS: WB-MRI provides high levels of diagnostic accuracy for both nodal and metastatic bone disease, with higher levels of sensitivity than BS for metastatic disease, and similar performance to 18F-choline PET/CT. T2 and post-contrast mDixon had no significant additive value above a protocol comprising mDixon and DWI alone. KEY POINTS: • A whole-body MRI protocol comprising unenhanced mDixon and diffusion-weighted imaging provides high levels of diagnostic accuracy for the primary staging of intermediate- and high-risk prostate cancer. • The diagnostic accuracy of whole-body MRI is much higher than that of bone scintigraphy, as currently recommended for clinical use. • Staging using WB-MRI, rather than bone scintigraphy, could result in better patient stratification and treatment delivery than is currently provided to patients worldwide.

Prostate cancer diagnostic pathway: Is a one-stop cognitive MRI targeted biopsy service a realistic goal in everyday practice? A pilot cohort in a tertiary referral centre in the UK.

OBJECTIVES: To evaluate the feasibility of a novel multiparametric MRI (mpMRI) and cognitive fusion transperineal targeted biopsy (MRTB) led prostate cancer (PCa) diagnostic service with regard to cancer detection and reducing time to diagnosis and treatment. DESIGN: Consecutive men being investigated for possible PCa under the UK 2-week wait guidelines. SETTING: Tertiary referral centre for PCa in the UK. PARTICIPANTS: Men referred with a raised prostate-specific antigen (PSA) or abnormal digital rectal examination between February 2015 and March 2016 under the UK 2-week rule guideline. INTERVENTIONS: An mpMRI was performed prior to patients attending clinic, on the same day. If required, MRTB was offered. Results were available within 48 hours and discussed at a specialist multidisciplinary team meeting. Patients returned for counselling within 7 days PRIMARY AND SECONDARY OUTCOME MEASURES: Outcome measures in this regard included the time to diagnosis and treatment of patients referred with a suspicion of PCa. Quality control outcome measures included clinically significant and total cancer detection rates. RESULTS: 112 men were referred to the service. 111 (99.1%) underwent mpMRI. Median PSA was 9.4 ng/mL (IQR 5.6-21.0). 87 patients had a target on mpMRI with 25 scoring Likert 3/5 for likelihood of disease, 26 4/5 and 36 5/5.57 (51%) patients received a local anaesthetic, Magnetic resonance imaging targeted biopsy (MRTB). Cancer was detected in 45 (79%). 43 (96%) had University College London definition 2 disease or greater. The times to diagnosis and treatment were a median of 8 and 20 days, respectively. CONCLUSIONS: This approach greatly reduces the time to diagnosis and treatment. Detection rates of significant cancer are high. Similar services may be valuable to patients with a potential diagnosis of PCa.

Magnetic resonance imaging in the early detection of prostate cancer and review of the literature on magnetic resonance imaging-stratified clinical pathways.

INTRODUCTION: With level 1 evidence now available on the diagnostic accuracy of multiparametric magnetic resonance imaging (MRI) we must now utilise this data in developing an MRI-stratified diagnostic pathway for the early detection of prostate cancer. Areas covered: A literature review was conducted and identified seven randomised control trials (RCT's) assessing the diagnostic accuracy of such a pathway against the previously accepted systematic/random trans-rectal ultrasound guided (TRUS) biopsy pathway. The studies were heterogeneous in their design. Five studies assessed the addition of MRI-targeted biopsies to a standard care systematic TRUS biopsy pathway. Three of these studies showed either an increase in their diagnostic accuracy or the potential to remove systematic biopsies. Two studies looked specifically at a targeted biopsy only pathway and although the results were again mixed, there was no decrease in the diagnostic rate and overall significantly fewer biopsy cores were taken in the MRI group. Expert commentary: Results from these RCT's together with multiple retrospective and prospective studies point towards either an improved diagnostic rate for clinically significant cancer and/or a reduction in the need for systematic biopsies with a MRI-stratified pathway. The challenge for the urological community will be to implement pre-biopsy MRI into a routine clinical pathway with likely independent monitoring of standards.

Focal salvage high-intensity focused ultrasound in radiorecurrent prostate cancer.

OBJECTIVE: To assess short- to medium-term cancer control rates and side effects of focal salvage high- intensity focused ultrasound (HIFU). MATERIALS AND METHODS: A retrospective registry analysis identified 150 men who underwent focal salvage HIFU (FS-HIFU) (Sonablate 500) between November 2006 and August 2015. Metastatic disease was excluded by nodal assessment on the pelvic MRI, a radioisotope bone scan and positron-emission tomography (PET) imaging (choline-18F-fluorodeoxyglucose PET or choline PET-CT). In our current clinical practice, metastatic disease must be excluded by both choline PET and bone scan. Localization of cancer was carried out using multiparametric MRI of the prostate (T2-weighted, diffusion-weighted and dynamic contrast-enhanced imaging) with systematic or template prostate mapping biopsies. The primary outcome was a composite failure incorporating biochemical failure (BCF) and/or positive localized or distant imaging results and/or positive biopsy and/or systemic therapy and/or metastases/prostate cancer-specific death. The secondary outcome was BCF using the Phoenix-ASTRO definition (prostate-specific antigen [PSA] nadir + 2 ng/mL). We used Kaplan-Meier analysis and Cox proportional hazards regression to quantify the effect of the determinants on the endpoints. RESULTS: The mean (standard deviation [sd]) patient age at focal salvage HIFU was 69.8 (6.1) years and the median (interquartile range [IQR]) PSA pre-focal salvage HIFU was 5.5 (3.6-7.9) ng/mL. The median (IQR) follow-up was 35 (22-52) months. Patients were classified as having low- 2.7% (4/150), intermediate- 39.3% (59/150) and high-risk disease 41.3% (62/150) according to D'Amico classification, prior to focal salvage HIFU. Composite failure occurred in 61% of patients (91/150) and BCF occurred in 51.3% (77/150). The Kaplan-Meier composite endpoint-free survival (CEFS) rate at 3 years was 40% (95% confidence interval [CI] 31-50) for the entire group. Kaplan-Meier estimates of CEFS were 100%, 49% and 24% at 3 years in the low-, intermediate- and high-risk groups pre-salvage HIFU, respectively. The Kaplan-Meier biochemical disease-free survival (BDFS) rate at 3 years was 48% (95% CI 39-59) for the entire group. Kaplan-Meier estimates of BDFS were 100%, 61% and 32% at 3 years in the low-, intermediate- and high-risk groups pre-salvage HIFU, respectively. Complications included urinary tract infection (11.3%; 17/150), bladder neck stricture (8%; 12/150), recto-urethral fistula after one HIFU procedure (2%; 3/150) and osteitis pubis (0.7%; 1/150). CONCLUSION: Focal salvage HIFU conferred a relatively low complication and side effect rate. CEFS and biochemical control in the short to medium term were reasonable, especially in this relatively high-risk cohort, but still low compared with current whole-gland salvage therapies. Focal salvage therapy may offer disease control in men at high risk whilst minimizing additional treatment morbidities.

Magnetic resonance imaging-transrectal ultrasound fusion focal cryotherapy of the prostate: A prospective development study.

OBJECTIVES: The use of software-based magnetic resonance-transrectal ultrasound fusion to deliver focal therapy may increase the precision of treatment. This is a prospective development study assessing the feasibility of Magnetic resonance imaging-transrectal ultrasound (MRI-TRUS) fusion focal cryotherapy. METHODS AND MATERIALS: Consecutive patients undergoing focal cryotherapy were included in an academic registry (December 2013-June 2014). MRI-TRUS fusion focal cryotherapy was offered to men with visible clinically significant prostate cancer (Galil SeedNet system). Eligibility was determined by multiparametric MRI (mpMRI), and transperineal template mapping or targeted biopsies. A rigid fusion platform (Biojet) was used with the operator ensuring the ice ball covered at least the lesion. Adverse events were scored using the NCICTC V4. Genitourinary toxicity was assessed using patient-reported outcome measures (IPSS, IIEF-15, and UCLA-EPIC). Early contrast-enhanced MRI and mpMRI at 6 to 12 months were used to assess extent of lesion ablation. RESULTS: Of 23 patients scheduled, 5 did not have image fusion owing to surgeon preference. Overall, 18 patients undergoing image-fusion cryotherapy had median age of 68 (interquartile range [IQR]: 65-73) years and median preoperative prostate-specific antigen = 9.54 (5.65-16)ng/ml. In all, 13 (72.2%) and 5 (27.8%) patients had intermediate and high-risk cancer, respectively. In total, 10 adverse events were reported with one of these as serious (grade 3) because of admission for hematuria requiring wash out only. There was no difference in the IIEF-15 between baseline and study end (P = 0.24). The IPSS remained stable (P = 0.12), whereas the UCLA-EPIC tended to improve (P = 0.065). The prostate-specific antigen level significantly decreased at 1.8 (1.04-2.93) ng/ml (P<0.001). Both early and late mpMRI showed no residual disease in the treated area. In 2 men, radiological progression of known contralateral disease was observed; both underwent focal high intensity focused ultrasound. CONCLUSION: MRI-TRUS fusion focal cryotherapy is feasible in most patients and seems to accurately guide ablation demonstrated by posttreatment imaging. Additional studies are needed to determine efficacy using postcryotherapy biopsy.

Population-based prediction of subject-specific prostate deformation for MR-to-ultrasound image registration.

Statistical shape models of soft-tissue organ motion provide a useful means of imposing physical constraints on the displacements allowed during non-rigid image registration, and can be especially useful when registering sparse and/or noisy image data. In this paper, we describe a method for generating a subject-specific statistical shape model that captures prostate deformation for a new subject given independent population data on organ shape and deformation obtained from magnetic resonance (MR) images and biomechanical modelling of tissue deformation due to transrectal ultrasound (TRUS) probe pressure. The characteristics of the models generated using this method are compared with corresponding models based on training data generated directly from subject-specific biomechanical simulations using a leave-one-out cross validation. The accuracy of registering MR and TRUS images of the prostate using the new prostate models was then estimated and compared with published results obtained in our earlier research. No statistically significant difference was found between the specificity and generalisation ability of prostate shape models generated using the two approaches. Furthermore, no statistically significant difference was found between the landmark-based target registration errors (TREs) following registration using different models, with a median (95th percentile) TRE of 2.40 (6.19) mm versus 2.42 (7.15) mm using models generated with the new method versus a model built directly from patient-specific biomechanical simulation data, respectively (N = 800; 8 patient datasets; 100 registrations per patient). We conclude that the proposed method provides a computationally efficient and clinically practical alternative to existing complex methods for modelling and predicting subject-specific prostate deformation, such as biomechanical simulations, for new subjects. The method may also prove useful for generating shape models for other organs, for example, where only limited shape training data from dynamic imaging is available.

Technological aspects of delivering cryotherapy for prostate cancer.

Since the era of prostate specific antigen (PSA) testing, there has been a stage and grade migration seen with prostate cancer along with a reduction in mortality. Subsequently, concerns have been raised about the over treatment of patients following the diagnosis of localized prostate cancers. Cryotherapy, in which extremely low temperatures induce cell death via multiple mechanisms, has seen a drastic improvement in its technology since the 1800s. Such advances have improved oncological outcomes while reducing complication rates. Furthermore, technological advances have allowed the development of focal cryotherapy which aims to reduce morbidity associated with more radical whole-gland therapies. There is growing evidence that focal cryotherapy provides good oncological and morbidity rates when compared with traditional radical/whole-gland therapies.

The PICTURE study -- prostate imaging (multi-parametric MRI and Prostate HistoScanning™) compared to transperineal ultrasound guided biopsy for significant prostate cancer risk evaluation.

OBJECTIVE: The primary objective of the PICTURE study is to assess the negative predictive value of multi-parametric MRI (mp-MRI) and Prostate HistoScanning™ (PHS) in ruling-out clinically significant prostate cancer. PATIENTS AND METHODS: PICTURE is a prospective diagnostic validating cohort study conforming to level 1 evidence. PICTURE will assess the diagnostic performance of multi-parametric Magnetic Resonance Imaging (mp-MRI) and Prostate HistoScanning™ (PHS) ultrasound. PICTURE will involve validating both index tests against a reference test, transperineal Template Prostate Mapping (TPM) biopsies, which can be applied in all men under evaluation. Men will be blinded to the index test results and both index tests will be reported prospectively prior to the biopsies being taken to ensure reporter blinding. Paired analysis of each of the index tests to the reference test will be done at patient level. Those men with an imaging lesion will undergo targeted biopsies to assess the clinical utility of sampling only suspicious areas. The study is powered to assess the negative predictive value of these imaging modalities in ruling-out clinically significant prostate cancer. DISCUSSION: The PICTURE study aims to assess the performance characteristics of two imaging modalities (mp-MRI and Prostate HistoScanning) for their utility in the prostate cancer pathway. PICTURE aims to identify if either imaging test may be useful for ruling out clinically significant disease in men under investigation, and also to examine if either imaging modality is useful for the detection of disease. Recruitment is underway and expected to complete in 2014.

Morbidity associated with primary high intensity focused ultrasound and redo high intensity focused ultrasound for localized prostate cancer.

PURPOSE: High intensity focused ultrasound may have a role as an alternative to standard radical therapies for localized prostate cancer. An attribute of high intensity focused ultrasound is that it can be repeated. We determined morbidity after primary and redo high intensity focused ultrasound. MATERIALS AND METHODS: We performed an academic lead analysis of United Kingdom registry data on high intensity focused ultrasound treatments at 3 centers using patient reported continence and sexual function outcomes. Validated questionnaires were completed before and after each ultrasound treatment. RESULTS: A total of 359 patients received 1 whole gland high intensity focused ultrasound treatment for localized prostate cancer from October 2004 to June 2012, of whom 130 (36.2%) received re-treatment. Median followup was 27 months (range 3 to 81) after re-treatment. When analyzing adverse events, 10.8% of patients experienced urinary tract infection after the first treatment compared to 3.9% after re-treatment (p=0.009). Urethral dilatation was required in 13.8% and 14.0% of patients after first and redo ultrasound treatments (p=0.7), and bladder neck incision was required in 9.2% and 11.6%, respectively (p=0.2). Before and after re-treatment 73.3% and 55.1% of patients had no leak, and 2.7% and 9.0% used daily pads (p<0.001 and p=0.07, respectively). Analysis of erectile function showed that 56.2% and 56.0% of patients were potent before and after re-treatment, respectively (p=0.9). CONCLUSIONS: Redo high intensity focused ultrasound is associated with an increase in urinary side effects but sexual side effects do not appear to be significantly increased. The number of adverse events seems to be equivalent after first and redo treatments. Meticulous patient selection is of paramount importance when selecting men for redo high intensity focused ultrasound.

Do low-grade and low-volume prostate cancers bear the hallmarks of malignancy?

Prostate cancer is generally multifocal and consists of a dominant focus-measured by tumour volume and deemed the index lesion-and one or more separate, secondary tumour foci of smaller volume. Much laboratory and clinical evidence has shown that we need to rethink how we regard low-grade and low-volume prostate lesions. In this Personal View, we discuss why small, low-grade Gleason pattern prostate lesions, which are currently designated as prostate cancer, could be regarded as non-malignant. These lesions either do not meet the criteria of the hallmarks of cancer or robust evidence that they do so is absent, by contrast with large lesions with a high Gleason grade, which seem to cause most metastatic disease.

Focal salvage therapy for localized prostate cancer recurrence after external beam radiotherapy: a pilot study.

BACKGROUND: The objective of this study was to evaluate the safety, feasibility, side-effect profile, and proof of concept for focal salvage therapy using high-intensity focused ultrasound (HIFU). METHODS: A registry-based analysis was conducted between 2004 and 2009 of 430 patients who underwent HIFU. Thirty-nine patients received focal salvage therapy for localized recurrence after external beam radiotherapy. Multiparametric magnetic resonance imaging studies combined with transperineal template prostate mapping biopsies or transrectal biopsies were used to localize disease. Validated questionnaires were used to assess functional outcomes. Biochemical failure was defined by using both Phoenix criteria (prostate-specific antigen [PSA] nadir plus 2 ng/mL) and Stuttgart criteria (PSA nadir plus 1.2 ng/mL). RESULTS: The mean pre-HIFU PSA level was 4.6 ng/mL. The median follow-up was 17 months (interquartile range, 10-29 months). International Index of Erectile Function-5 scores decreased from a median ± standard deviation (SD) of 18 ± 16 to 13 ± 21 at 6 months, demonstrating worsening function. Scores on the University of California Los Angeles-Expanded Prostate Cancer Index Composite Urinary domain indicate that pad-free, leak-free continence status was 64%, and the pad-free rate was 87.2% at last follow-up. One rectourethral fistula occurred and spontaneously resolved with urinary and bowel diversion. The actuarial progression-free survival rate (including PSA nonresponders) was 69% at 1 year and 49% at 2 years according to Phoenix criteria. Excluding PSA nonresponders, these rates were 74% and 58%, respectively (Phoenix criteria). CONCLUSIONS: The results from this study indicated that focal salvage therapy is a potential strategy for localized recurrence after radiotherapy that may reduce the harms resulting from whole-gland salvage therapies.

The accuracy of different biopsy strategies for the detection of clinically important prostate cancer: a computer simulation.

PURPOSE: The true accuracy of different biopsy strategies for detecting clinically significant prostate cancer is unknown, given the positive evaluation bias required for verification by radical prostatectomy. To evaluate how well different biopsy strategies perform at detecting clinically significant prostate cancer we used computer simulation in cystoprostatectomy cases with cancer. MATERIALS AND METHODS: A computer simulation study was performed on prostates acquired at radical cystoprostatectomy. A total of 346 prostates were processed and examined for prostate cancer using 3 mm whole mount slices. The 96 prostates that contained cancer were digitally reconstructed. Biopsy simulations incorporating various degrees of random localization error were performed using the reconstructed 3-dimensional prostate computer model. Each biopsy strategy was simulated 500 times. Two definitions of clinically significant prostate cancer were used to define the reference standard, including definition 1--Gleason score 7 or greater, and/or lesion volume 0.5 ml or greater and definition 2--Gleason score 7 or greater, and/or lesion volume 0.2 ml or greater. RESULTS: A total of 215 prostate cancer foci were present. The ROC AUC to detect and rule out definition 1 prostate cancer was 0.69, 0.75, 0.82 and 0.91 for 12-core transrectal ultrasound biopsy with a random localization error of 15 and 10 mm, 14-core transrectal ultrasound biopsy and template prostate mapping using a 5 mm sampling frame, respectively. CONCLUSIONS: To our knowledge our biopsy simulation study is the first to evaluate the performance of different sampling strategies to detect clinically important prostate cancer in a population that better reflects the demographics of a screened cohort. Compared to other strategies standard transrectal ultrasound biopsy performs poorly for detecting clinically important cancer. Marginal improvement can be achieved using additional cores placed anterior but the performance attained by template prostate mapping is optimal.