mpMRI Scans Research Articles

Poster 6 - MRI for clinically suspected prostate cancer – the disparity between private and public sectors

There is increasing evidence to implement multiparametric magnetic resonance imaging (mpMRI) for biopsy-naive men with clinically suspected prostate cancer (PCa). This will reduce the number of unnecessary trans rectal ultrasound biopsies (TRUS-Bx) performed and reduce the number of indolent cancers diagnosed. To assess current clinical practices for investigating clinically suspected prostate cancer in Ireland and determine if private health insurance providers are offering mpMRI scans in biopsy-naive men. Each health insurance provider procedure code was reviewed. The indications and requirements for prostate mpMRI in the setting of diagnosis, staging, surveillance, and recurrence were assessed for each health care provider. Current practices adopted by accredited referral clinics for suspected prostate cancer were reviewed. Two of the three leading health insurance providers, which between them cover 46% of the private health insurance market in Ireland, provide pre-biopsy mpMRI cover as of April 2019. This leaves almost half of those insured with no accessibility to pre-biopsy mpMRI. This is in contrast to the majority of public NCCP hospitals that offer pre-biopsy mpMRI for clinically suspected prostate cancer. Pre-biopsy mpMRI for clinically suspected prostate cancer is emerging as a standard of practice in Ireland. International guidelines are also changing to reflect latest clinical trial evidence. Private health insurance providers should amend their policies to reflect current clinical practices already adopted in the public sector.

Validation and physiological association of changes in magnetic resonance imaging radiomic features in response to androgen deprivation therapy in patients with high-risk prostate cancer.

43 Background: Biochemical response to neoadjuvant androgen deprivation therapy (nADT) predicts relapse-free and overall survival for prostate cancer (PCa). Radiomic features change in response to nADT, showing potential as prognostic imaging biomarkers. Using multi-parametric MRI (mpMRI) before and after nADT, we aim to validate these changes, evaluate reproducibility and assess their association with previously described ADT-induced reductions in quantitative blood flow (BF) and blood volume (BV) imaging parameters. Methods: 20 patients with high-risk PCa received 4 mpMRI scans, 2 pre-nADT and 2 after 3 months therapy. T2-weighted sequences were used to define tumour regions-of-interest (ROI) which were subtracted from the prostate outline to form the benign prostate ROI. Established kinetic models were applied to dynamic contrast susceptibility MR sequences to derive changes in BF and BV in both ROI. Pyradiomics was used to extract homogeneity and energy features from both ROI. A paired student T-test compared feature values pre- and post-nADT. An inter-class correlation coefficient (ICC) calculated using mean values from consecutive scans assessed reproducibility. Feature changes and physiological parameters were correlated using Pearson’s coefficient. Results: In response to nADT, homogeneity and energy values significantly increased in benign prostate (p < 0.001) and decreased in tumour (p < 0.005). Both features exhibited high reproducibility pre- and post-nADT; all ICC ≥0.89. The reduction in tumour homogeneity and energy showed a positive association with the decline in BF and BV induced by ADT; all r 0.69-0.78, all p < 0.001. No correlation was seen in benign prostate. Conclusions: Energy and homogeneity radiomic features in benign and malignant prostate are reproducible and show significant reciprocal change in response to nADT. Validation of these changes and the strong association in tumour with ADT-induced physiological effects confirms their potential as prognostic biomarkers in high-risk PCa.

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

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

Prostate Cancer Risk Assessment in Biopsy-naïve Patients: The Rotterdam Prostate Cancer Risk Calculator in Multiparametric Magnetic Resonance Imaging-Transrectal Ultrasound (TRUS) Fusion Biopsy and Systematic TRUS Biopsy

BackgroundThe value of multiparametric magnetic resonance imaging (mpMRI) and targeted biopsy (TBx) remains controversial for biopsy-naïve men when compared to transrectal ultrasound (TRUS)-guided systematic biopsy (SBx). Risk-based patient selection could help to selectively identify men with significant prostate cancer (PCa) and thus reduce unnecessary mpMRI and biopsies. ObjectivesTo compare PCa detection rates for mpMRI TBx with SBx and to determine the rate of potentially avoided mpMRI and biopsies through risk-based selection using the Rotterdam Prostate Cancer Risk Calculator (RPCRC). Design, setting, and participantsTwo-hundred consecutive biopsy-naïve men in two centres underwent mpMRI scanning, 12-core SBx, and subsequent MRI-TRUS TBx in the case of suspicious lesion(s) (Prostate Imaging-Reporting and Data System v.2 score ≥3). Outcome measurements and statistical analysisWe measured the detection rate for high-grade (Gleason score ≥ 3+4) PCa for TBx and SBx. We carried out a retrospective stratification according to RPCRC biopsy advice to determine the rate of mpMRI and biopsies that could potentially be avoided by RPCRC-based patient selection in relation to the rate of high-grade PCa missed. Results and limitationsTBx yielded high-grade PCa in 51 men (26%) and low-grade PCa in 14 men (7%), while SBx yielded high-grade PCa in 63 men (32%) and low-grade PCa in 41 men (21%). Four out of 73 men (5%) with negative RPCRC advice and 63 out of 127 men (50%) with positive advice had high-grade PCa. Upfront RPCRC-based patient selection for mpMRI and TBx would have avoided 73 out of 200 (37%) mpMRI scans, missing two out of 51 (4%) high-grade PCas. Limitations include the RPCRC definition of high- and low-grade PCa and different mpMRI techniques. ConclusionsmpMRI with TBx detected PCa with high Gleason score and avoided biopsy in low-grade PCa, but failed to detect all high-grade PCa when compared to SBx among biopsy-naïve men. Risk-based patient selection using the RPCRC can avoid one-third of mpMRI scans and SBx in biopsy-naïve men. Patient summaryMen with a suspicion of prostate cancer are increasingly undergoing a magnetic resonance imaging (MRI) scan. Although promising, MRI-targeted biopsy is not accurate enough to safely replace systematic prostate biopsy for now. Individualised assessment of prostate cancer risk using the Rotterdam Prostate Cancer Risk Calculator could avoid one-third of MRI scans and systematic prostate biopsies.

AB206. 135. Comparing MRI PIRADS v2 scores and template biopsies of the prostate over time

Background: Globally prostate cancer is a major health concern. Increasing longevity among populations and improved diagnostics has led to significantly increased detection rates. The use of multi parametric MRI (mpMRI) as an adjunct to diagnosis and surveillance is now common practice in prostate cancer. In 2012 the Prostate Imaging, Reporting and Data System (PIRADS) and subsequent revised version in 2015, PIRADS v2, were introduced to help categorize mpMRI reporting. We investigate the correlation between mpMRI scan results and template guided, sector mapping prostate biopsy performed by a single urologist and its evolution over time.

A urinary biomarker‐based risk score correlates with multiparametric MRI for prostate cancer detection

Prostate cancer (PCa) diagnostics would greatly benefit from more accurate, non-invasive techniques for the detection of clinically significant disease, leading to a reduction of over-diagnosis and over-treatment. The aim of this study was to determine the association between a novel urinary biomarker-based risk score (SelectMDx), multiparametric MRI (mpMRI) outcomes, and biopsy results for PCa detection. This retrospective observational study used data from the validation study of the SelectMDx score, in which urine was collected after digital rectal examination from men undergoing prostate biopsies. A subset of these patients also underwent a mpMRI scan of the prostate. The indications for performing mpMRI were based on persistent clinical suspicion of PCa or local staging after PCa was found upon biopsy. All mpMRI images were centrally reviewed in 2016 by an experienced radiologist blinded for the urine test results and biopsy outcome. The PI-RADS version 2 was used. In total, 172 patients were included for analysis. Hundred (58%) patients had PCa detected upon prostate biopsy, of which 52 (52%) had high-grade disease correlated with a significantly higher SelectMDx score (P < 0.01). The median SelectMDx score was significantly higher in patients with a suspicious significant lesion on mpMRI compared to no suspicion of significant PCa (P < 0.01). For the prediction of mpMRI outcome, the area-under-the-curve of SelectMDx was 0.83 compared to 0.66 for PSA and 0.65 for PCA3. There was a positive association between SelectMDx score and the final PI-RADS grade. There was a statistically significant difference in SelectMDx score between PI-RADS 3 and 4 (P < 0.01) and between PI-RADS 4 and 5 (P < 0.01). The novel urinary biomarker-based SelectMDx score is a promising tool in PCa detection. This study showed promising results regarding the correlation between the SelectMDx score and mpMRI outcomes, outperforming PCA3. Our results suggest that this risk score could guide clinicians in identifying patients at risk for significant PCa and selecting patients for further radiological diagnostics to reduce unnecessary procedures.

Assessment of free-hand transperineal targeted prostate biopsy using multiparametric magnetic resonance imaging-transrectal ultrasound fusion in Chinese men with prior negative biopsy and elevated prostate-specific antigen

BackgroundTo evaluate the role of free-hand transperineal targeted prostate biopsy using multiparametric magnetic resonance imaging-transrectal ultrasound (mpMRI-TRUS) fusion in Chinese men with repeated biopsy.MethodsA total of 101 consecutive patients suspicious of prostate cancer (PCa) at the mpMRI scan and with prior negative biopsy and elevated PSA values were prospectively recruited at two urological centers. Suspicious areas on mpMRI were defined and graded using PI-RADS score. Targeted biopsies (TB) were performed for each suspicious lesion and followed a 12-core systematic biopsy (SB). Results of biopsy pathology and whole-gland pathology at prostatectomy were analyzed and compared between TB and SB. The risk for biopsy positivity was assessed by univariate and multivariate logistic regression analysis.ResultsFusion biopsy revealed PCa in 41 of 101 men (40.6%) and 25 (24.8%) were clinically significant. There was exact agreement between TB and SB in 74 (73.3%) men. TB diagnosed 36% more significant cancer than SB (22 vs 13 cases, P = 0.012). When TB were combined with SB, an additional 14 cases (34.1%) of mostly significant PCa (71.4%) were diagnosed (P = 0.036). TB had greater sensitivity and accuracy for significant cancer than SB in 26 men with whole-gland pathology after prostatectomy. PI-RADS score on mpMRI was the most powerful predictor of PCa and significant cancer.ConclusionsFree-hand transperineal TB guided with MRI-TRUS fusion imaging improves detection of clinical significant PCa in Chinese men with previously negative biopsy. PI-RADS score is a reliable predictor of PCa and significant cancer.

A non-invasive and adaptive CAD system to detect brain tumor from T2-weighted MRIs using customized Otsu’s thresholding with prominent features and supervised learning

The detection of brain tumor is a challenging task for radiologists as brain is the most complicated and complex organ. This work presents a non-invasive and adaptive method for detection of tumor from T2-weighted brain magnetic resonance (MR) images. Non-homogeneous brain MR images are enhanced by preprocessing and segmented through multilevel customization of Otsu’s thresholding technique. Several textural and shape features are extracted from the segmented image and two prominent ones are selected through entropy measure. Support vector machine (SVM) classifies MR images using prominent features. Experiments are performed on a dataset collected from MP MRI & CT Scan Centre at NSCB Medical College Jabalpur and the other from Charak Diagnostic & Research Centre Jabalpur. More than 98% accuracy is reported with 100% sensitivity for both the datasets at 99% confidence interval. The proposed system is compared with several existing methods to showcase its efficacy.

Evaluation of the changing landscape of prostate cancer diagnosis and management from 2005 to 2016.

BackgroundApproaches to prostate cancer (PCa) diagnosis and treatment have evolved significantly over past decades. There has been an increasing focus on minimizing overdiagnosis and overtreatment of clinically insignificant PCa. The objective of this study was to evaluate the changes in the diagnostic approach and initial treatment strategy that has evolved over time in an Australian urological private practice.Materials and methodsMen with newly diagnosed PCa were identified from the private practice electronic and paper medical records from 2005 to 2016 and data was consolidated into six groups of 2-year intervals. Diagnostic strategy was analyzed with particular reference to the use of multiparametric magnetic resonance imaging (mpMRI) scan and 68Ga-prostate specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) scans. National Comprehensive Cancer Network risk group stratification was correlated with initial treatment strategy and compared over time.ResultsChart review identified 839 men who had a mean age of 65.8 years. In 2011–2012, prebiopsy mpMRI scan was introduced. Its uptake correlated with a decrease in numbers of men diagnosed with low risk cancer (r = -0.80, P = 0.04) and an increase in numbers of men diagnosed with high-risk cancer (r = 0.90, P = 0.01). The use of 68Ga-PSMA PET/CT was associated with decreasing use of CT and bone scans performed. Open radical prostatectomy had a declining trend particularly when robotic surgery (robotic assisted radical prostatectomy (RARP)) was introduced. Pelvic lymph node dissections performed progressively decreased. An increased use of luteinizing hormone receptor hormone (LHRH) antagonists was seen in favor of LHRH agonists. Whilst use of high dose rate brachytherapy declined, there was an increased use of low dose rate brachytherapy.ConclusionPrebiopsy mpMRI has been associated with an increased proportion of newly diagnosed men having clinically significant PCa. Over time, 68Ga-PSMA PET/CT scans, robotic assisted radical prostatectomy (RARP) and LHRH antagonists have increased in use, whilst CT and bone scans, and pelvic lymph node dissections have decreased.

PD65-10 USING MP-MRI GUIDED PROSTATE NEEDLE BIOPSY SAMPLES TO IMPROVE PROSTATE CANCER DIAGNOSIS.

You have accessJournal of UrologyProstate Cancer: Markers II1 Apr 2017PD65-10 USING MP-MRI GUIDED PROSTATE NEEDLE BIOPSY SAMPLES TO IMPROVE PROSTATE CANCER DIAGNOSIS. Jonathan OLIVIER, Jonathan Kay, Vasili Stravinides, Freeman Alex, Hashim Ahmed, Caroline Moore, Emberton Mark, and Whitaker Hayley Jonathan OLIVIERJonathan OLIVIER More articles by this author , Jonathan KayJonathan Kay More articles by this author , Vasili StravinidesVasili Stravinides More articles by this author , Freeman AlexFreeman Alex More articles by this author , Hashim AhmedHashim Ahmed More articles by this author , Caroline MooreCaroline Moore More articles by this author , Emberton MarkEmberton Mark More articles by this author , and Whitaker HayleyWhitaker Hayley More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2017.02.2960AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES Prostate cancer is a heterogeneous disease both in terms of clinical presentation and pathology which can lead to very different clinical outcomes. Conventional prognostic factors, including serum PSA levels, Gleason score and pathological stage are often inaccurate and histological biomarkers could be useful in distinguishing indolent from aggressive prostate cancers. Tissue microarrays (TMAs) are useful for validating protein biomarker expression in large cohorts of patient samples using immunohistochemistry (IHC) but are often created from radical prostatectomy specimens which do not accurately represent diagnostic biopsies. The limited tumour availability in biopsy samples has led us to develop an improved method for constructing TMAs to study multiple biomarkers simultaneously on biopsy tissues. Objectives: Validate a new method of constructing TMA blocks from prostate needle biopsies and study the link between well known biomarkers (PSA, PSMA, p63,MSMB and AMACR) and mp-MRI data METHODS Patients attending UCLH with suspected prostate cancer were recruited to the PICTURE study and underwent a diagnostic mp-MRI scan and subsequent image-guided biopsy. This was analysed by a pathologist to confirm tumour Grade. Clinical and MRI data were routinely collected. We extracted the regions of tumour within biopsy samples and re-embedded them so that they could easily be repositioned into a recipient TMA block. Blocks were sectioned and stained using automated IHC for established prostate cancer biomarkers including p63, AMACR, PSMA, MSMB and PSA. RESULTS We have successfully produced TMA blocks containing representative regions of benign and tumour samples for 200 patients. 99.4% of the cores included were recovered in the TMAs slides. Biomarker expression correlates with Grade of cancer for PSA (p=0.01), MSMB (p=0.016) p63 (p<0.0001), AMACR (p<0.0001) and PSMA (p<0.0001). Expression also correlates with Likert score for PSMA (p=0.009), p63 (p=0.023) and AMACR (p<0.0001). CONCLUSIONS This new method of constructing TMA blocks is effective at utilising interesting regions of biopsy tissue. It allows multiple biomarkers to be assessed quickly from large cohort studies that accurately represent the tissue routinely used for diagnosis. © 2017FiguresReferencesRelatedDetails Volume 197Issue 4SApril 2017Page: e1270 Advertisement Copyright & Permissions© 2017MetricsAuthor Information Jonathan OLIVIER More articles by this author Jonathan Kay More articles by this author Vasili Stravinides More articles by this author Freeman Alex More articles by this author Hashim Ahmed More articles by this author Caroline Moore More articles by this author Emberton Mark More articles by this author Whitaker Hayley More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Toward Prostate Cancer Contouring Guidelines on Magnetic Resonance Imaging: Dominant Lesion Gross and Clinical Target Volume Coverage Via Accurate Histology Fusion

Defining prostate cancer (PCa) lesion clinical target volumes (CTVs) for multiparametric magnetic resonance imaging (mpMRI) could support focal boosting or treatment to improve outcomes or lower morbidity, necessitating appropriate CTV margins for mpMRI-defined gross tumor volumes (GTVs). This study aimed to identify CTV margins yielding 95% coverage of PCa tumors for prospective cases with high likelihood. Twenty-five men with biopsy-confirmed clinical stage T1 or T2 PCa underwent pre-prostatectomy mpMRI, yielding T2-weighted, dynamic contrast-enhanced, and apparent diffusion coefficient images. Digitized whole-mount histology was contoured and registered to mpMRI scans (error ≤2mm). Four observers contoured lesion GTVs on each mpMRI scan. CTVs were defined by isotropic and anisotropic expansion from these GTVs and from multiparametric (unioned) GTVs from 2 to 3 scans.Histologic coverage (proportions of tumor area on co-registered histology inside the CTV, measured for Gleason scores [GSs] ≥6 and≥7) and prostate sparing (proportions of prostate volume outside the CTV) were measured. Nonparametric histologic-coverage prediction intervals defined minimal margins yielding 95% coverage for prospective cases with 78% to 92% likelihood. On analysis of 72 true-positive tumor detections, 95% coverage margins were 9 to 11mm (GS≥6) and 8 to 10mm (GS≥7) for single-sequence GTVs and were 8mm (GS≥6) and 6mm (GS≥7) for 3-sequence GTVs, yielding CTVs that spared 47% to 81% of prostate tissue for the majority of tumors. Inclusion of T2-weighted contours increased sparing for multiparametric CTVs with 95% coverage margins for GS ≥6, and inclusion of dynamic contrast-enhanced contours increased sparing for GS ≥7. Anisotropic 95% coverage margins increased the sparing proportions to 71% to 86%. Multiparametric magnetic resonance imaging-defined GTVs expanded by appropriate margins may support focal boosting or treatment of PCa; however, these margins, accounting for interobserver and intertumoral variability, may preclude highly conformal CTVs. Multiparametric GTVs and anisotropic margins may reduce the required margins and improve prostate sparing.

Validating multiparametric MRI for diagnosis and monitoring of prostate cancer in patients for active surveillance

To compare multiparametric magnetic resonance imaging (mpMRI) with transrectal ultrasound-guided prostate biopsy (TRUS-bx) for the diagnosis and monitoring of small-volume prostate cancer (PCa) in patients on active surveillance (AS). In a retrospective cross-sectional validation study, 100 patients on AS for PCa underwent a systematic 12-core TRUS-bx (the gold standard) as well as mpMRI, on either a 1.5 or 3 Tesla scanner (32 and 68 patients, respectively). Three pathologists reported biopsy histology separately. A single, experienced radiologist scored mpMRI scans using the PI-RADS system. We compared left- and right-sided PI-RADS scores of the peripheral zone with TRUS-bx results of the relevant prostate lobe. We then estimated the specificity and sensitivity of mpMRI in diagnosing low-grade low-risk PCa in our AS cohort. The sensitivity of mpMRI was 37% (95% CI 28-47%) and specificity was 85% (CI 76-92%) for cancer. The negative predictive value was 51% (CI 44-60%), and the positive predictive value was 76% (CI 62-87%). The positive and negative likelihood ratios were 2.5 and 0.7, respectively. Because of its low specificity and low negative predictive value, mpMRI is not suitable for diagnosing low-grade small-volume PCa. However, because of a specificity of 85% and a negative likelihood ratio of 0.7, mpMRI may be useful for follow-up of previously TRUS-bx diagnosed patients who are on AS.

Role of serial multiparametric magnetic resonance imaging in prostate cancer active surveillance

To examine whether addition of 3T multiparametric magnetic resonance imaging (mpMRI) to an active surveillance protocol could detect aggressive or progressive prostate cancer. Twenty-three patients with low risk disease were enrolled on this active surveillance study, all of which had Gleason score 6 or less disease. All patients had clinical assessments, including digital rectal examination and prostate specific antigen (PSA) testing, every 6 mo with annual 3T mpMRI scans with gadolinium contrast and minimum sextant prostate biopsies. The MRI images were anonymized of patient identifiers and clinical information and each scan underwent radiological review without the other results known. Descriptive statistics for demographics and follow-up as well as the sensitivity and specificity of mpMRI to identify prostate cancer and progressive disease were calculated. During follow-up (median 24.8 mo) 11 of 23 patients with low-risk prostate cancer had disease progression and were taken off study to receive definitive treatment. Disease progression was identified through upstaging of Gleason score on subsequent biopsies for all 11 patients with only 2 patients also having a PSA doubling time of less than 2 years. All 23 patients had biopsy confirmed prostate cancer but only 10 had a positive index of suspicion on mpMRI scans at baseline (43.5% sensitivity). Aggressive disease prediction from baseline mpMRI scans had satisfactory specificity (81.8%) but low sensitivity (58.3%). Twenty-two patients had serial mpMRI scans and evidence of disease progression was seen for 3 patients all of whom had upstaging of Gleason score on biopsy (30% specificity and 100% sensitivity). Addition of mpMRI imaging in active surveillance decision making may help in identifying aggressive disease amongst men with indolent prostate cancer earlier than traditional methods.

Risk-based Patient Selection for Magnetic Resonance Imaging-targeted Prostate Biopsy after Negative Transrectal Ultrasound-guided Random Biopsy Avoids Unnecessary Magnetic Resonance Imaging Scans

BackgroundMultiparametric magnetic resonance imaging (mpMRI) is increasingly used in men with suspicion of prostate cancer (PCa) after negative transrectal ultrasound (TRUS)-guided random biopsy. Risk-based patient selection for mpMRI could help to avoid unnecessary mpMRIs. ObjectiveTo study the rate of potentially avoided mpMRIs after negative TRUS-guided random biopsy by risk-based patient selection using the Rotterdam Prostate Cancer Risk Calculator (RPCRC). Design, setting, and participantsOne hundred and twenty two consecutive men received a mpMRI scan and subsequent MRI-TRUS fusion targeted biopsy in case of suspicious lesion(s) (Prostate Imaging Reporting and Data System ≥ 3) after negative TRUS-guided random biopsy. Men were retrospectively stratified according to the RPCRC biopsy advice to compare targeted biopsy outcomes after risk-based patient selection with standard (prostate specific antigen and/or digital rectal examination-driven) patient selection. Outcome measurements and statistical analysisThe rate of potentially avoided mpMRIs by RPCRC-based patient selection in relation to the rate of missed high-grade (Gleason ≥ 3+4) PCa. Receiver operating characteristic curve analysis was performed to determine the area under the curve of the RPCRC for (high-grade) PCa. Results and limitationsOf the 60 men with a positive biopsy advice, six (10%) had low-grade PCa and 28 (47%) had high-grade PCa in targeted biopsy. Of the 62 men with a negative advice, two (3%) had low-grade PCa and three (5%) had high-grade PCa. Upfront RPCRC-based patient selection would have avoided 62 (51%) of 122 mpMRIs and two (25%) of eight low-grade PCa diagnoses, missing three (10%) of 31 high-grade PCa. The area under the curve of the RPCRC for PCa and high-grade PCa was respectively 0.76 (95% confidence interval 0.67–0.85) and 0.84 (95% confidence interval 0.76–0.93). ConclusionsRisk-based patient selection with the RPCRC can avoid half of mpMRIs after a negative prostate specific antigen and/or digital rectal examination-driven TRUS-guided random biopsy. Further improvement in risk-based patient selection for mpMRI could be made by adjusting the RPCRC for MRI-targeted biopsy outcome prediction. Patient summaryThe suspicion of prostate cancer remains in many men after a negative ultrasound-guided prostate biopsy. These men increasingly receive an often unnecessary magnetic resonance imaging (MRI) scan. We found that patient selection for MRI based on the Rotterdam Prostate Cancer Risk Calculator biopsy advice could avoid half of the MRIs.

Transperineal targeted prostate biopsy with real-time fusion imaging of multiparametric magnetic resonance imaging and transrectal ultrasound

Objective To evaluate the value of transperineal targeted biopsy with real-time fusion images of transrectal ultrasound (TRUS) and multiparametric magnetic resonance imaging (mpMRI) for the diagnosis of prostate cancer (PCa). Methods Clinical and imaging data of 62 consecutive patients suspected of PCa at the mpMRI scan and PSA>4.0 μg/L were retrospectively analyzed. Targeted biopsies (TB) were carried out for each cancer-suspicious lesion, and followed a systematic 12-core biopsy (SB) protocol. Pathological findings of TB and SB were analyzed. Results The age of the patients was (68.38±6.57)years (range 51-79 years). The preoperative PSA value was (10.21±5.57)μg/L (range 4.5-30.1 μg/L). Preoperative prostate volume was (34.05±9.86)ml (range 19-64 ml). The PCa patients detected by SB and/or TB were 34 (54.8%). Cancer-detected rates of SB and TB cores were 7.53% and 26.2%, respectively (P<0.001). The positive core length of SB and TB cores were (3.71±2.77)mm (range 1-14 mm) and (5.00±3.04)mm (range 2-17 mm), respectively (P=0.016). The positive core percent of SB and TB cores were (28.77±20.13)% (range 7-100%) and (35.76±18.73)% (range 11%-100%), respectively (P=0.048). Moreover, clinically cores detected by the SB and TB for final diagnosis of PCa were 19 cores (2.6%) and 48 cores (18.5%), respectively (P<0.001). Conclusions Transperineal TB using real-time TRUS and mpMRI fusion imaging can improve sampling quality and elevate clinically detection rate of PCa when application combined with SB. Key words: Endosonography; Magnetic resonance imaging; Fusion image; Prostatic neoplasms; Biopsy, needle

Free-hand transperineal targeted prostate biopsy with real-time fusion imaging of multiparametric magnetic resonance imaging and transrectal ultrasound: single-center experience in China.

To report our experience with free-hand transperineal targeted biopsy with real-time transrectal ultrasound (TRUS) and multiparametric magnetic resonance imaging (mpMRI) fusion images for the diagnosis of prostate cancer (PCa). A total of 62 consecutive patients suspicious of PCa at the mpMRI scan and PSA >4.0 ng/mL were recruited prospectively. Targeted biopsies (TBs) were carried out for each cancer-suspicious lesion and followed a 12-core systematic biopsy (SB) protocol. Pathological findings of TB and SB were analyzed. The age of the patients was 68.38 ± 6.57 years (range 51-79 years). The preoperative PSA value was 10.21 ± 5.57 ng/mL (range 4.5-30.1 ng/mL). Preoperative prostate volume was 34.05 ± 9.86 mL (range 19-64 mL). The PCa patients detected by SB and/or TB were 34 (54.8%). Cancer-detected rates of SB and TB cores were 7.53 and 26.2%, respectively (P < 0.001). The positive core length of SB and TB cores was 3.71 ± 2.77 mm (range 1-14 mm) and 5.00 ± 3.04 mm (range 2-17 mm), respectively (P = 0.016). The positive core percent of SB and TB cores was 28.77 ± 20.13% (range 7-100%) and 35.76 ± 18.73 (range 11-100%), respectively (P = 0.048). Moreover, clinically significant PCa cores detected by the SB and TB were 19 cores (2.6%) and 48 cores (18.5%), respectively (P < 0.001). Free-hand transperineal TB using real-time TRUS and mpMRI fusion imaging has the ability to improve sampling quality and detect more clinically significant PCa compared with SB.

Delivering Multiparametric MRI-Guided High-Dose-Rate Brachytherapy Boost in Nonmetastatic Prostate Cancer

In localized prostate cancer, dominant intra-prostatic lesions (DiLs) of gross tumor are thought to drive metastatic potential. Tumour control and overall cancer control may be improved if DiLs are targeted with escalated radiation dose. This pilot study investigated the feasibility of focal high dose rate (HDR) brachytherapy boost in a cohort of patients treated with combined EBRT and HDR brachytherapy. Multi-parametric MRI (mp-MRI) was used and feasibility assessed in terms of (i) whether tumor tissue can be identified using mp-MRI (ii) the focal boost dose that can be delivered to the tumor within normal tissue dose constraints and (iii) treatment related toxicities. Thirty patients were recruited and mp-MRI scans performed in the week before HDR brachytherapy treatment. For focal boost treatment plans, focal-planning target volumes (F-PTVs) were identified which were the visible tumor plus a margin of 4.5mm, constrained to the prostate capsule. F-PTV dose was boosted as much as possible while maintaining standard treatment planning objectives (prescribed dose 15Gy to the whole prostate in one fraction) and normal tissue dose constraints. For the first 15 patients, focal boost treatment plans were produced retrospectively. For the subsequent 15 patients the focal boost treatment was delivered if an F-PTV could be identified from the mp-MRI data. Gastro-intestinal and genitourinary toxicity was recorded using CTCAE v4.0 at 6 weeks and then 3 monthly intervals following treatment. In the retrospective study F-PTVs were identified for all 15 patients and focal boost treatment plans achieved mean F-PTV D90 of 21.4 Gy compared to 17.8 Gy in the delivered treatments. In the subsequent cohort of patients, no tumor was visible in the mp-MRI data for 3 patients, 2 patients were determined to be unfit for surgery after the MRI scan and 2 were unable to have scans for logistical reasons. 8 patients received the focal boost treatment with dose escalated to achieve mean F-PTV D90 of 22.0 Gy. Dose escalation had no impact on urethra D10 (mean 17.1 Gy) and increased rectal D2cc by 3% (to 8.9 Gy). In the patients treated with F-PTV boost no Grade 3 toxicities were seen and 3 of 8 patients had Grade 2 or less toxicity in the first 3 months. Multi-parametric MRI guided HDR prostate brachytherapy tumour boost is feasible. It is possible to identify tumour regions within the prostate in the majority of patients, and to achieve significant increased dose to DiLs without violating urethral and rectal dose constraints or increasing treatment induced toxicities.