Acceptability of magnetic resonance imaging for prostate cancer diagnosis with patients and GPs: a qualitative interview study.

BACKGROUND: Magnetic resonance imaging (MRI) of the prostate is a new, more accurate, non-invasive test for prostate cancer diagnosis. AIM: To understand the acceptability of MRI for patients and GPs for prostate cancer diagnosis. DESIGN AND SETTING: Qualitative study of men who had undergone a prostate MRI for possible prostate cancer, and GPs who had referred at least one man for possible prostate cancer in the previous 12 months in West London and Devon. METHOD: Semi-structured interviews, conducted in person or via telephone, were audio-recorded and transcribed verbatim. Deductive thematic analysis was undertaken using Sekhon's Theoretical Framework of Acceptability, retrospectively for patients and prospectively for GPs. RESULTS: Twenty-two men (12 from Devon, age range 47-80 years), two patients' partners, and 10 GPs (6 female, age range 36-55 years) were interviewed. Prostate MRI was broadly acceptable for most patient participants, and they reported that it was not a significant undertaking to complete the scan. GPs were more varied in their views on prostate MRI, with a broad spectrum of knowledge and understanding of prostate MRI. Some GPs expressed concerns about additional clinical responsibility and local availability of MRI if direct access to prostate MRI in primary care were to be introduced. CONCLUSION: Prostate MRI appears to be acceptable to patients. Some differences were found between patients in London and Devon, mainly around burden of testing and opportunity costs. Further exploration of GPs' knowledge and understanding of prostate MRI could inform future initiatives to widen access to diagnostic testing in primary care.

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.

An Evaluation of Screening Pathways Using a Combination of Magnetic Resonance Imaging and Prostate-specific Antigen: Results from the IP1-PROSTAGRAM Study.

BACKGROUND: The use of prostate-specific antigen (PSA) testing to screen for prostate cancer has been fraught with under- and overdiagnosis. Short, noncontrast magnetic resonance imaging (MRI) might detect more grade group ≥2 cancers with similar rates of biopsy. OBJECTIVE: To evaluate strategies that combined PSA and MRI to select men based in the community for a prostate biopsy. DESIGN, SETTING, AND PARTICIPANTS: IP1-PROSTAGRAM was a prospective, population-based, paired cohort study of 408 men aged 50-69 yr conducted at seven UK primary care practice and two imaging centres (from October 10, 2018 to May 15, 2019). INTERVENTION: All participants underwent screening with a PSA test, MRI (T2-weighted and diffusion), and transrectal ultrasound (b-mode and elastography). If any test was screen positive, a systematic 12-core biopsy was performed. Additional image-fusion targeted biopsies were taken if the MRI or ultrasound was positive. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: We conducted an analysis, set out in the statistical plan a priori, comparing 13 different pathways including PSA-alone, MRI-alone, and a range of PSA thresholds and MRI scores. The performance of each pathway was evaluated focusing on the trade-offs between biopsy referral rates and detection of grade group ≥2 cancers. A targeted biopsy was performed only where the PROSTAGRAM MRI showed a lesion score of 3, 4, or 5. RESULTS AND LIMITATIONS: The standard PSA pathway (PSA ≥3 ng/ml + systematic biopsy) would lead to 10% of men being referred for a biopsy and a 1.0% detection rate of grade group ≥2 cancers. Pathways that relied on MRI alone set at a threshold score of 3 for a biopsy led to higher biopsy rates, but with benefit of high cancer detection rates. The pathway that combined an initial low PSA threshold (≥1.0 ng/ml) and MRI score ≥4 accurately identified a high rate of grade group ≥2 cancers (2.5%, 95% confidence interval 1.3-4.6) while recommending fewer patients for a biopsy (7.1%, 95% confidence interval 4.9-10.2). The results are pertinent to only one screening round, the impact of repeat screening rounds is not evaluated, and the required MRI capacity is currently lacking. CONCLUSIONS: Our results highlight the trade-off that exists between reducing excessive numbers of biopsies and maintaining grade group ≥2 cancer detection rates. A pathway that combines PSA ≥1 ng/ml and MRI score ≥4 maintains the detection of grade group ≥2 cancers while recommending fewer men for biopsies and would be the preferred strategy to evaluate in future studies at the first screening round. PATIENT SUMMARY: The IP1-PROSTAGRAM study shows that PROSTAGRAM magnetic resonance imaging in men with a prostate-specific antigen level of ≥1.0 ng/ml could be a promising pathway to evaluate in future screening trials.

Perceived patient burden and acceptability of MRI in comparison to PSA and ultrasound: results from the IP1-PROSTAGRAM study.

BACKGROUND: The IP1-PROSTAGRAM study showed that a short, non-contrast MRI detected more significant cancers with similar rates of biopsy compared to PSA. Herein, we compare the expected and perceived burden of PSA, MRI and ultrasound as screening tests. METHODS: IP1-PROSTAGRAM was a prospective, population-based, paired screening study of 408 men conducted at seven UK primary care practices and two imaging centres. The screening tests were serum PSA, non-contrast MRI and ultrasound. If any test was screen-positive, a prostate biopsy was performed. Participants completed an Expected Burden Questionnaire (EBQ) and Perceived Burden Questionnaire (PBQ) before and after each screening test. RESULTS: The overall level of burden for MRI and PSA was minimal. Few men reported high levels of anxiety, burden, embarrassment or pain following either MRI or PSA. Participants indicated an overall preference for MRI after completing all screening tests. Of 408 participants, 194 (47.5%) had no preference, 106 (26.0%) preferred MRI and 79 (19.4%) preferred PSA. This indicates that prior to screening, participants preferred MRI compared to PSA (+6.6%, 95% CI 4.4-8.4, p = 0.02) and after completing screening, the preference for MRI was higher (+21.1%, 95% CI 14.9-27.1, p < 0.001). The proportion of participants who strongly agreed with repeating the test was 50.5% for ultrasound, 65% for MRI and 68% for PSA. A larger proportion of participants found ultrasound anxiety-inducing, burdensome, embarrassing and painful compared to both MRI and PSA. CONCLUSIONS: Prostagram MRI and PSA are both acceptable as screening tests among men aged 50-69 years. Both tests were associated with minimal amounts of anxiety, burden, embarrassment and pain. The majority of participants preferred MRI over PSA and ultrasound. REGISTRATION: This study was registered on clinicaltrials.gov at https://clinicaltrials.gov/ct2/show/NCT03702439 .

Circulating Chromosome Conformation Signatures Significantly Enhance PSA Positive Predicting Value and Overall Accuracy for Prostate Cancer Detection.

BACKGROUND: Prostate cancer (PCa) has a high lifetime prevalence (one out of six men), but currently there is no widely accepted screening programme. Widely used prostate specific antigen (PSA) test at cut-off of 3.0 ng/mL does not have sufficient accuracy for detection of any prostate cancer, resulting in numerous unnecessary prostate biopsies in men with benign disease and false reassurance in some men with PCa. We have recently identified circulating chromosome conformation signatures (CCSs, Episwitch® PCa test) allowing PCa detection and risk stratification in line with standards of clinical PCa staging. The purpose of this study was to determine whether combining the Episwitch PCa test with the PSA test will increase its diagnostic accuracy. METHODS: n = 109 whole blood samples of men enrolled in the PROSTAGRAM screening pilot study and n = 38 samples of patients with established PCa diagnosis and cancer-negative controls from Imperial College NHS Trust were used. Samples were tested for PSA, and the presence of CCSs in the loci encoding for of DAPK1, HSD3B2, SRD5A3, MMP1, and miRNA98 associated with high-risk PCa identified in our previous work. RESULTS: PSA > 3 ng/mL alone showed a low positive predicted value (PPV) of 0.14 and a high negative predicted value (NPV) of 0.93. EpiSwitch alone showed a PPV of 0.91 and a NPV of 0.32. Combining PSA and Episwitch tests has significantly increased the PPV to 0.81 although reducing the NPV to 0.78. Furthermore, integrating PSA, as a continuous variable (rather than a dichotomised 3 ng/mL cut-off), with EpiSwitch in a new multivariant stratification model, Prostate Screening EpiSwitch (PSE) test, has yielded a remarkable combined PPV of 0.92 and NPV of 0.94 when tested on the independent prospective cohort. CONCLUSIONS: Our results demonstrate that combining the standard PSA readout with circulating chromosome conformations (PSE test) allows for significantly enhanced PSA PPV and overall accuracy for PCa detection. The PSE test is accurate, rapid, minimally invasive, and inexpensive, suggesting significant screening diagnostic potential to minimise unnecessary referrals for expensive and invasive MRI and/or biopsy testing. Further extended prospective blinded validation of the new combined signature in a screening cohort with low cancer prevalence would be the recommended step for PSE adoption in PCa screening.

Landmarks in the evolution of prostate biopsy.

Approaches and techniques used for diagnostic prostate biopsy have undergone considerable evolution over the past few decades: from the original finger-guided techniques to the latest MRI-directed strategies, from aspiration cytology to tissue core sampling, and from transrectal to transperineal approaches. In particular, increased adoption of transperineal biopsy approaches have led to reduced infectious complications and improved antibiotic stewardship. Furthermore, as image fusion has become integral, these novel techniques could be incorporated into prostate biopsy methods in the future, enabling 3D-ultrasonography fusion reconstruction, molecular targeting based on PET imaging and autonomous robotic-assisted biopsy.

The rapid assessment for prostate imaging and diagnosis (RAPID) prostate cancer diagnostic pathway.

OBJECTIVE: To report outcomes within the Rapid Assessment for Prostate Imaging and Diagnosis (RAPID) diagnostic pathway, introduced to reduce patient and healthcare burdens and standardize delivery of pre-biopsy multiparametric magnetic resonance imaging (MRI) and transperineal biopsy. PATIENTS AND METHODS: A total of 2130 patients from three centres who completed the RAPID pathway (3 April 2017 to 31 March 2020) were consecutively entered as a prospective registry. These patients were also compared to a pre-RAPID cohort of 2435 patients. Patients on the RAPID pathway with an MRI score 4 or 5 and those with PSA density ≥0.12 and an MRI score 3 were advised to undergo a biopsy. Primary outcomes were rates of biopsy and cancer detection. Secondary outcomes included comparison of transperineal biopsy techniques, patient acceptability and changes in time to diagnosis before and after the introduction of RAPID. RESULTS: The median patient age and PSA level were 66 years and 6.6 ng/mL, respectively. Biopsy could be omitted in 43% of patients (920/2130). A further 7.9% of patients (168/2130) declined a recommendation for biopsy. The percentage of biopsies avoided among sites varied (45% vs 36% vs 51%; P < 0.001). In all, 30% (221/742) had a local anaesthetic (grid and stepper) transperineal biopsy. Clinically significant cancer detection (any Gleason score ≥3 + 4) was 26% (560/2130) and detection of Gleason score 3 + 3 alone constituted 5.8% (124/2130); detection of Gleason score 3 + 3 did not significantly vary among sites (P = 0.7). Among participants who received a transperineal targeted biopsy, there was no difference in cancer detection rates among local anaesthetic, sedation and general anaesthetic groups. In the 2435 patients from the pre-RAPID cohor, time to diagnosis was 32.1 days (95% confidence interval [CI] 29.3-34.9) compared to 15.9 days (95% CI 12.9-34.9) in the RAPID group. A total of 141 consecutive patient satisfaction surveys indicated a high satisfaction rate with the pathway; 50% indicated a preference for having all tests on a single day. CONCLUSIONS: The RAPID prostate cancer diagnostic pathway allows 43% of men to avoid a biopsy while preserving good detection of clinically significant cancers and low detection of insignificant cancers, although there were some centre-level variations.

Predicting the Need for Biopsy to Detect Clinically Significant Prostate Cancer in Patients with a Magnetic Resonance Imaging-detected Prostate Imaging Reporting and Data System/Likert ≥3 Lesion: Development and Multinational External Validation of the Imperial Rapid Access to Prostate Imaging and Diagnosis Risk Score.

BACKGROUND: Although multiparametric magnetic resonance imaging (MRI) has high sensitivity, its lower specificity leads to a high prevalence of false-positive lesions requiring biopsy. OBJECTIVE: To develop and externally validate a scoring system for MRI-detected Prostate Imaging Reporting and Data System (PIRADS)/Likert ≥3 lesions containing clinically significant prostate cancer (csPCa). DESIGN, SETTING, AND PARTICIPANTS: The multicentre Rapid Access to Prostate Imaging and Diagnosis (RAPID) pathway included 1189 patients referred to urology due to elevated age-specific prostate-specific antigen (PSA) and/or abnormal digital rectal examination (DRE); April 27, 2017 to October 25, 2019. INTERVENTION: Visual-registration or image-fusion targeted and systematic transperineal biopsies for an MRI score of ≥4 or 3 + PSA density ≥0.12 ng/ml/ml. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Fourteen variables were used in multivariable logistic regression for Gleason ≥3 + 4 (primary) and Gleason ≥4 + 3, and PROMIS definition 1 (any ≥4 + 3 or ≥6 mm any grade; secondary). Nomograms were created and a decision curve analysis (DCA) was performed. Models with varying complexity were externally validated in 2374 patients from six international cohorts. RESULTS AND LIMITATIONS: The five-item Imperial RAPID risk score used age, PSA density, prior negative biopsy, prostate volume, and highest MRI score (corrected c-index for Gleason ≥3 + 4 of 0.82 and 0.80-0.86 externally). Incorporating family history, DRE, and Black ethnicity within the eight-item Imperial RAPID risk score provided similar outcomes. The DCA showed similar superiority of all models, with net benefit differences increasing in higher threshold probabilities. At 20%, 30%, and 40% of predicted Gleason ≥3 + 4 prostate cancer, the RAPID risk score was able to reduce, respectively, 11%, 21%, and 31% of biopsies against 1.8%, 6.2%, and 14% of missed csPCa (or 9.6%, 17%, and 26% of foregone biopsies, respectively). CONCLUSIONS: The Imperial RAPID risk score provides a standardised tool for the prediction of csPCa in patients with an MRI-detected PIRADS/Likert ≥3 lesion and can support the decision for prostate biopsy. PATIENT SUMMARY: In this multinational study, we developed a scoring system incorporating clinical and magnetic resonance imaging characteristics to predict which patients have prostate cancer requiring treatment and which patients can safely forego an invasive prostate biopsy. This model was validated in several other countries.

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.

Direct mail from primary care and targeted recruitment strategies achieved a representative uptake of prostate cancer screening.

BACKGROUND AND OBJECTIVES: Prostate cancer screening studies has previously not been able to reflect a diverse group of participants. We evaluated a range of recruitment strategies and their ability to recruit from the Black population and areas of deprivation. METHODS: IP1-PROSTAGRAM was a prospective, population-based, paired screening study of 408 participants conducted at seven UK primary care practices and two imaging centres. All participants underwent screening with a prostate specific antigen (PSA) test, magnetic resonance imaging (MRI), and transrectal ultrasound. A number of recruitment strategies were embedded including direct mail, media campaigns, and a targeted recruitment strategy to increase participation among harder-to-reach groups. RESULTS: A total of 1,316 expressions of interest were received (20th September 2018 to 15th May 2019). The direct mail strategy generated 317 expressions of interest from 1707 invitation letters. Overall 387 expressions of interest were received following the targeted strategy and 612 from media campaigns. The recruitment target was met 19 months ahead of the schedule. Of the 411 participants, ethnicity was White (38.0%), Black (32.4%), Asian (23.0%), and Other/Mixed (4.4%) ethnic groups. This higher recruitment of Black men was driven by the targeted recruitment strategy. A comparison of recruitment methods showed marked differences between ethnicities recruited (P < 0.001). The proportion of Black participants recruited by direct mail (8%) was similar to the prevalence of Black local population (9%) whereas, targeted recruitment was 88% (115) and media recruitment 1.7% (1). The Index of Multiple Deprivation (IMD) distribution was similar to the local population with marginal higher recruitment from more deprived areas; proportion increasing from 26% to 40% from least to most deprived IMD quintiles (Quintiles 4/5 vs. 1/2). Direct mail recruited a close-to-normal distribution for deprivation with targeted recruitment trending towards recruiting from most deprived areas. CONCLUSION: Direct mail and targeted strategies designed to engage a diverse population can achieve a representative uptake from Black participants and those from a lower socioeconomic group.

Multiparametric ultrasound versus multiparametric MRI to diagnose prostate cancer (CADMUS): a prospective, multicentre, paired-cohort, confirmatory study.

BACKGROUND: Multiparametric MRI of the prostate followed by targeted biopsy is recommended for patients at risk of prostate cancer. However, multiparametric ultrasound is more readily available than multiparametric MRI. Data from paired-cohort validation studies and randomised, controlled trials support the use of multiparametric MRI, whereas the evidence for individual ultrasound methods and multiparametric ultrasound is only derived from case series. We aimed to establish the overall agreement between multiparametric ultrasound and multiparametric MRI to diagnose clinically significant prostate cancer. METHODS: We conducted a prospective, multicentre, paired-cohort, confirmatory study in seven hospitals in the UK. Patients at risk of prostate cancer, aged 18 years or older, with an elevated prostate-specific antigen concentration or abnormal findings on digital rectal examination underwent both multiparametric ultrasound and multiparametric MRI. Multiparametric ultrasound consisted of B-mode, colour Doppler, real-time elastography, and contrast-enhanced ultrasound. Multiparametric MRI included high-resolution T2-weighted images, diffusion-weighted imaging (dedicated high B 1400 s/mm2 or 2000 s/mm2 and apparent diffusion coefficient map), and dynamic contrast-enhanced axial T1-weighted images. Patients with positive findings on multiparametric ultrasound or multiparametric MRI underwent targeted biopsies but were masked to their test results. If both tests yielded positive findings, the order of targeting at biopsy was randomly assigned (1:1) using stratified (according to centre only) block randomisation with randomly varying block sizes. The co-primary endpoints were the proportion of positive lesions on, and agreement between, multiparametric MRI and multiparametric ultrasound in identifying suspicious lesions (Likert score of ≥3), and detection of clinically significant cancer (defined as a Gleason score of ≥4 + 3 in any area or a maximum cancer core length of ≥6 mm of any grade [PROMIS definition 1]) in those patients who underwent a biopsy. Adverse events were defined according to Good Clinical Practice and trial regulatory guidelines. The trial is registered on ISRCTN, 38541912, and ClinicalTrials.gov, NCT02712684, with recruitment and follow-up completed. FINDINGS: Between March 15, 2016, and Nov 7, 2019, 370 eligible patients were enrolled; 306 patients completed both multiparametric ultrasound and multiparametric MRI and 257 underwent a prostate biopsy. Multiparametric ultrasound was positive in 272 (89% [95% CI 85-92]) of 306 patients and multiparametric MRI was positive in 238 patients (78% [73-82]; difference 11·1% [95% CI 5·1-17·1]). Positive test agreement was 73·2% (95% CI 67·9-78·1; κ=0·06 [95% CI -0·56 to 0·17]). Any cancer was detected in 133 (52% [95% CI 45·5-58]) of 257 patients, with 83 (32% [26-38]) of 257 being clinically significant by PROMIS definition 1. Each test alone would result in multiparametric ultrasound detecting PROMIS definition 1 cancer in 66 (26% [95% CI 21-32]) of 257 patients who had biopsies and multiparametric MRI detecting it in 77 (30% [24-36]; difference -4·3% [95% CI -8·3% to -0·3]). Combining both tests detected 83 (32% [95% CI 27-38]) of 257 clinically significant cancers as per PROMIS definition 1; of these 83 cancers, six (7% [95% CI 3-15]) were detected exclusively with multiparametric ultrasound, and 17 (20% [12-31]) were exclusively detected by multiparametric MRI (agreement 91·1% [95% CI 86·9-94·2]; κ=0·78 [95% CI 0·69-0·86]). No serious adverse events were related to trial activity. INTERPRETATION: Multiparametric ultrasound detected 4·3% fewer clinically significant prostate cancers than multiparametric MRI, but it would lead to 11·1% more patients being referred for a biopsy. Multiparametric ultrasound could be an alternative to multiparametric MRI as a first test for patients at risk of prostate cancer, particularly if multiparametric MRI cannot be carried out. Both imaging tests missed clinically significant cancers detected by the other, so the use of both would increase the detection of clinically significant prostate cancers compared with using each test alone. FUNDING: The Jon Moulton Charity Trust, Prostate Cancer UK, and UCLH Charity and Barts Charity.

Adjusting for verification bias in diagnostic accuracy measures when comparing multiple screening tests - an application to the IP1-PROSTAGRAM study.

INTRODUCTION: Novel screening tests used to detect a target condition are compared against either a reference standard or other existing screening methods. However, as it is not always possible to apply the reference standard on the whole population under study, verification bias is introduced. Statistical methods exist to adjust estimates to account for this bias. We extend common methods to adjust for verification bias when multiple tests are compared to a reference standard using data from a prospective double blind screening study for prostate cancer. METHODS: Begg and Greenes method and multiple imputation are extended to include the results of multiple screening tests which determine condition verification status. These two methods are compared to the complete case analysis using the IP1-PROSTAGRAM study data. IP1-PROSTAGRAM used a paired-cohort double-blind design to evaluate the use of imaging as alternative tests to screen for prostate cancer, compared to a blood test called prostate specific antigen (PSA). Participants with positive imaging (index) and/or PSA (control) underwent a prostate biopsy (reference standard). RESULTS: When comparing complete case results to Begg and Greenes and methods of multiple imputation there is a statistically significant increase in the specificity estimates for all screening tests. Sensitivity estimates remained similar across the methods, with completely overlapping 95% confidence intervals. Negative predictive value (NPV) estimates were higher when adjusting for verification bias, compared to complete case analysis, even though the 95% confidence intervals overlap. Positive predictive value (PPV) estimates were similar across all methods. CONCLUSION: Statistical methods are required to adjust for verification bias in accuracy estimates of screening tests. Expanding Begg and Greenes method to include multiple screening tests can be computationally intensive, hence multiple imputation is recommended, especially as it can be modified for low prevalence of the target condition.

Cancer Control Outcomes Following Focal Therapy Using High-intensity Focused Ultrasound in 1379 Men with Nonmetastatic Prostate Cancer: A Multi-institute 15-year Experience.

BACKGROUND: Focal therapy aims to treat areas of cancer to confer oncological control whilst reducing treatment-related functional detriment. OBJECTIVE: To report oncological outcomes and adverse events following focal high-intensity focused ultrasound (HIFU) for treating nonmetastatic prostate cancer. DESIGN, SETTING, AND PARTICIPANTS: An analysis of 1379 patients with ≥6 mo of follow-up prospectively recorded in the HIFU Evaluation and Assessment of Treatment (HEAT) registry from 13 UK centres (2005-2020) was conducted. Five or more years of follow-up was available for 325 (24%) patients. Focal HIFU therapy used a transrectal ultrasound-guided device (Sonablate; Sonacare Inc., Charlotte, NC, USA). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Failure-free survival (FFS) was primarily defined as avoidance of no evidence of disease to require salvage whole-gland or systemic treatment, or metastases or prostate cancer-specific mortality. Differences in FFS between D'Amico risk groups were determined using a log-rank analysis. Adverse events were reported using Clavien-Dindo classification. RESULTS AND LIMITATIONS: The median (interquartile range) age was 66 (60-71) yr and prostate-specific antigen was 6.9 (4.9-9.4) ng/ml with D'Amico intermediate risk in 65% (896/1379) and high risk in 28% (386/1379). The overall median follow-up was 32 (17-58) mo; for those with ≥5 yr of follow-up, it was 82 (72-94). A total of 252 patients had repeat focal treatment due to residual or recurrent cancer; overall 92 patients required salvage whole-gland treatment. Kaplan-Meier 7-yr FFS was 69% (64-74%). Seven-year FFS in intermediate- and high-risk cancers was 68% (95% confidence interval [CI] 62-75%) and 65% (95% CI 56-74%; p = 0.3). Clavien-Dindo >2 adverse events occurred in 0.5% (7/1379). The median 10-yr follow-up is lacking. CONCLUSIONS: Focal HIFU in carefully selected patients with clinically significant prostate cancer, with six and three of ten patients having, respectively, intermediate- and high-risk cancer, has good cancer control in the medium term. PATIENT SUMMARY: Focal high-intensity focused ultrasound treatment to areas of prostate with cancer can provide an alternative to treating the whole prostate. This treatment modality has good medium-term cancer control over 7 yr, although 10-yr data are not yet available.

Population-Based Prostate Cancer Screening With Magnetic Resonance Imaging or Ultrasonography: The IP1-PROSTAGRAM Study.

IMPORTANCE: Screening for prostate cancer using prostate-specific antigen (PSA) testing can lead to problems of underdiagnosis and overdiagnosis. Short, noncontrast magnetic resonance imaging (MRI) or transrectal ultrasonography might overcome these limitations. OBJECTIVE: To compare the performance of PSA testing, MRI, and ultrasonography as screening tests for prostate cancer. DESIGN, SETTING, AND PARTICIPANTS: This prospective, population-based, blinded cohort study was conducted at 7 primary care practices and 2 imaging centers in the United Kingdom. Men 50 to 69 years of age were invited for prostate cancer screening from October 10, 2018, to May 15, 2019. INTERVENTIONS: All participants underwent screening with a PSA test, MRI (T2 weighted and diffusion), and ultrasonography (B-mode and shear wave elastography). The tests were independently interpreted without knowledge of other results. Both imaging tests were reported on a validated 5-point scale of suspicion. If any test result was positive, a systematic 12-core biopsy was performed. Additional image fusion-targeted biopsies were performed if the MRI or ultrasonography results were positive. MAIN OUTCOMES AND MEASURES: The main outcome was the proportion of men with positive MRI or ultrasonography (defined as a score of 3-5 or 4-5) or PSA test (defined as PSA ≥3 µg/L) results. Key secondary outcomes were the number of clinically significant and clinically insignificant cancers detected if each test was used exclusively. Clinically significant cancer was defined as any Gleason score of 3+4 or higher. RESULTS: A total of 2034 men were invited to participate; of 411 who attended screening, 408 consented to receive all screening tests. The proportion with positive MRI results (score, 3-5) was higher than the proportion with positive PSA test results (72 [17.7%; 95% CI, 14.3%-21.8%] vs 40 [9.9%; 95% CI, 7.3%-13.2%]; P < .001). The proportion with positive ultrasonography results (score, 3-5) was also higher than the proportion of those with positive PSA test results (96 [23.7%; 95% CI, 19.8%-28.1%]; P < .001). For an imaging threshold of score 4 to 5, the proportion with positive MRI results was similar to the proportion with positive PSA test results (43 [10.6%; 95% CI, 7.9%-14.0%]; P = .71), as was the proportion with positive ultrasonography results (52 [12.8%; 95% CI, 9.9%-16.5%]; P = .15). The PSA test (≥3 ng/mL) detected 7 clinically significant cancers, an MRI score of 3 to 5 detected 14 cancers, an MRI score of 4 to 5 detected 11 cancers, an ultrasonography score of 3 to 5 detected 9 cancer, and an ultrasonography score of 4 to 5 detected 4 cancers. Clinically insignificant cancers were diagnosed by PSA testing in 6 cases, by an MRI score of 3 to 5 in 7 cases, an MRI score of 4 to 5 in 5 cases, an ultrasonography score of 3 to 5 in 13 cases, and an ultrasonography score of 4 to 5 in 7 cases. CONCLUSIONS AND RELEVANCE: In this cohort study, when screening the general population for prostate cancer, MRI using a score of 4 or 5 to define a positive test result compared with PSA alone at 3 ng/mL or higher was associated with more men diagnosed with clinically significant cancer, without an increase in the number of men advised to undergo biopsy or overdiagnosed with clinically insignificant cancer. There was no evidence that ultrasonography would have better performance compared with PSA testing alone.

Assessment of Return to Baseline Urinary and Sexual Function Following Primary Focal Cryotherapy for Nonmetastatic Prostate Cancer.

BACKGROUND: The oncological outcomes in men with clinically significant prostate cancer following focal cryotherapy are promising, although functional outcomes are under-reported. OBJECTIVE: To determine the impact of focal cryotherapy on urinary and sexual function, specifically assessing return to baseline function. DESIGN, SETTING, AND PARTICIPANTS: Between October 2013 and November 2016, 58 of 122 men who underwent focal cryotherapy for predominantly anterior clinically significant localised prostate cancer within a prospective registry returned patient-reported outcome measure questionnaires, which included International Prostate Symptom Score (IPSS) and International Index of Erectile Function (IIEF-15) questionnaires. INTERVENTION: Standard cryotherapy procedure using either the SeedNet or the Visual-ICE cryotherapy system. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Primary outcome was return to baseline function of IPSS score and IIEF erectile function (EF) subdomain. Cumulative incidence and Cox-regression analyses were performed. RESULTS AND LIMITATIONS: Probability of returning to baseline IPSS function was 78% at 12 mo and 87% at both 18 and 24 mo, with recovery seen up to 18 mo. For IIEF (EF domain), the probability of returning to baseline function was 85% at 12 mo and 89% at both 18 and 24 mo, with recovery seen up to 18 mo. Only the preoperative IIEF-EF score was associated with a poor outcome (hazard ratio 0.96, 95% confidence interval 0.93-0.999, p = 0.04). The main limitation was that only half of the patients returned their questionnaires. CONCLUSIONS: In men undergoing primary focal cryotherapy, there is a high degree of preservation of urinary and erectile function with return to baseline function occurring from 3 mo and continuing up to 18 mo after focal cryotherapy. PATIENT SUMMARY: In men who underwent focal cryotherapy for prostate cancer, approximately nine in 10 returned to their baseline urinary and sexual function. Keeping in mind that level 1 evidence and long-term data are still needed, in men who wish to preserve urinary and sexual function, focal cryotherapy may be considered an alternative treatment option to radical therapy.

A Comparison of Prostate Cancer Detection between Visual Estimation (Cognitive Registration) and Image Fusion (Software Registration) Targeted Transperineal Prostate Biopsy.

PURPOSE: We compared clinically significant prostate cancer detection by visual estimation and image fusion targeted transperineal prostate biopsy. MATERIALS AND METHODS: This multicenter study included patients with multiparametric magnetic resonance imaging lesions undergoing visual estimation or image fusion targeted transperineal biopsy (April 2017-March 2020). Propensity score matching was performed using demographics (age and ethnicity), clinical features (prostate specific antigen, prostate volume, prostate specific antigen density and digital rectal examination), multiparametric magnetic resonance imaging variables (number of lesions, PI-RADS® score, index lesion diameter, whether the lesion was diffuse and radiological T stage) and biopsy factors (number of cores, operator experience and anesthetic type). Matched groups were compared overall and by operator grade, PI-RADS score, lesion multiplicity, prostate volume and anesthetic type using targeted-only and targeted plus systematic histology. Multiple clinically significant prostate cancer thresholds were evaluated (primary: Gleason ≥3+4). RESULTS: A total of 1,071 patients with a median age of 67.3 years (IQR 61.3-72.4), median prostate specific antigen of 7.5 ng/ml (IQR 5.3-11.2) and 1,430 total lesions underwent targeted-only biopsies (visual estimation: 372 patients, 494 lesions; image fusion: 699 patients, 936 lesions). A total of 770 patients with a median age of 67.4 years (IQR 61-72.1), median prostate specific antigen of 7.1 ng/ml (IQR 5.2-10.6) and 919 total lesions underwent targeted plus systematic biopsies (visual estimation: 271 patients, 322 lesions; image fusion: 499 patients, 597 lesions). Matched comparisons demonstrated no overall difference in clinically significant prostate cancer detection between visual estimation and image fusion (primary: targeted-only 54% vs 57.4%, p=0.302; targeted plus systematic 51.2% vs 58.2%, p=0.123). Senior urologists had significantly higher detection rates using image fusion (primary: targeted-only 45.4% vs 63.7%, p=0.001; targeted plus systematic 39.4% vs 64.5%, p <0.001). CONCLUSIONS: We found no overall difference in clinically significant prostate cancer detection, although image fusion may be superior in experienced hands.

Use of Imaging to Optimise Prostate Cancer Tumour Volume Assessment for Focal Therapy Planning.

PURPOSE OF REVIEW: Rapid advances in imaging of the prostate have facilitated the development of focal therapy and provided a non-invasive method of estimating tumour volume. Focal therapy relies on an accurate estimate of tumour volume for patient selection and treatment planning so that the optimal energy dose can be delivered to the target area(s) of the prostate while minimising toxicity to surrounding structures. This review provides an overview of different imaging modalities which may be used to optimise tumour volume assessment and critically evaluates the published evidence for each modality. RECENT FINDINGS: Multi-parametric MRI (mp-MRI) has become the standard tool for patient selection and guiding focal therapy treatment. The current evidence suggests that mp-MRI may underestimate tumour volume, although there is a large variability in results. There remain significant methodological challenges associated with pathological processing and accurate co-registration of histopathological data with mp-MRI. Advances in different ultrasound modalities are showing promise but there has been limited research into tumour volume estimation. The role of PSMA PET/CT is still evolving and further investigation is needed to establish if this is a viable technique for prostate tumour volumetric assessment. mp-MRI provides the necessary tumour volume information required for selecting patients and guiding focal therapy treatment. The potential for underestimation of tumour volume should be taken into account and an additional margin applied to ensure adequate treatment coverage. At present, there are no other viable image-based alternatives although advances in new technologies may refine volume estimations in the future.

Rethinking prostate cancer screening: could MRI be an alternative screening test?

In the past decade rigorous debate has taken place about population-based screening for prostate cancer. Although screening by serum PSA levels can reduce prostate cancer-specific mortality, it is unclear whether the benefits outweigh the risks of false-positive results and overdiagnosis of insignificant prostate cancer, and it is not recommended for population-based screening. MRI screening for prostate cancer has the potential to be analogous to mammography for breast cancer or low-dose CT for lung cancer. A number of potential barriers and technical challenges need to be overcome in order to implement such a programme. We discuss different approaches to MRI screening that could address these challenges, including abbreviated MRI protocols, targeted MRI screening, longer rescreening intervals and a multi-modal screening pathway. These approaches need further investigation, and we propose a phased stepwise research framework to ensure proper evaluation of the use of a fast MRI examination as a screening test for prostate cancer.