1、多参数MR在前列腺诊断和主动监测中的应用MR imaging of prostate gland2Start Here:PZ or TZ?PZTZ1235411235412354DCE-DWI1-4DCE+DWI 5PI-RADS v2,201420032016Clinical applications of prostate MRIInitial diagnosisTumor detectionLocalization CharacterizationRisk stratificationLocoregional stagingGuide for biopsySurveillanceGuid
2、e for surgery,focal therapy and radiation therapyAssessment of suspected recurrence3Excessive variation in the performance,interpretation,and reporting of prostate MRI examsPI-RADS AdMeTech foundation International prostate MRI working gorup2007 ESUR working group of prostate MR2010 ESUR develops PI
3、-RADS v1 ACR,ESUR&AdMeTech join forces2011 PI-RADS v1 published(Eur Radiol 2012;22:746-7572012 PI-RADS v2 announced2014Outline SECTION I Clinical Considerations and Technical SpecificationsSECTION II Normal Anatomy and Benign FindingsSECTION III Assessment and ReportingSECTION IV Multiparametric MRI
4、(mpMRI)SECTION V Staging5Initiation of PI-RADS Promote global standardization Diminish variation in Acquisition Interpretation Reporting A“living”document that will evolve as clinical experience and scientific data accrue6PI-RADS v2 needs to be tested and validated forspecific research and clinical
5、applicationsPurpose of PIRADS Establish minimum acceptable technical parameters for prostate mpMRI Simplify and standardize the terminology and content of radiology reports Develop assessment categories that summarize levels of suspicion or risk and can be used to select patients for biopsies and ma
6、nagement(e.g.,observation strategy vs.immediate intervention)7Facilitate the use of MRI data for targeted biopsyProstate Imaging and Reporting and Data System:Version 2Outline SECTION I Clinical Considerations and Technical SpecificationsSECTION II Normal Anatomy and Benign FindingsSECTION III Asses
7、sment and ReportingSECTION IV Multiparametric MRI(mpMRI)SECTION V Staging9Scan protocol常规序列常规序列方向方向范围范围层厚层厚采集参数采集参数层面内分辨率层面内分辨率其他要求其他要求T1WI轴位前列腺+精囊腺T2WI轴位矢状位冠状位前列腺+精囊腺FOV：12-20cm3mm无间距0.7mm（相位编码方向）0.4mm（频率编码方向）DWI/ADC轴位前列腺+精囊腺FOV：16-22cm4mm无间距TE:90ms,TR:3000ms2.5mm高b值1400sec/mm2重建ADC图，计算ADC值DCE轴位前列腺
8、+精囊腺3mm无间距TR:100ms,TE:7(including 3+4 with prominent but not predominant Gleason 4 component),and/or Volume 0.5cc,and/or Extraprostatic extension(EPE)13PI-RADS v2 Assessment Categories Very low(clinically significant cancer is highly unlikely to be present)PIRADS 1 Low(clinically significant cancer
9、is unlikely to be present)PIRADS 2 Intermediate(the presence of clinically significant cancer is equivocal)PIRADS 3 High(clinically significant cancer is likely to be present)PIRADS 4 Very high(clinically significant cancer is highly likely to be present)PIRADS 5 14Start Here:PZ or TZ?PZTZ1235412354
10、12354DCE-DWI1-4DCE+DWI 5Multi-parametric imagingReporting Measurement of the Prostate Gland Mapping Lesions Measurement of Lesions Caveats for Overall Assessment17Outline SECTION I Clinical Considerations and Technical SpecificationsSECTION II Normal Anatomy and Benign FindingsSECTION III Assessment
11、 and ReportingSECTION IV Multiparametric MRI(mpMRI)SECTION V Staging18Section V:Staging19Imaging features used to assess for EPE Asymmetry or invasion of the neurovascular bundles Bulging prostatic contour Irregular or spiculated margin Obliteration of the rectoprostatic angle Tumor-capsule interfac
12、e of greater than 1.0 cm Breach of the capsule20The apex of the prostate should be carefully inspected.Seminal vesicle invasion Demonstration of direct tumor extension from the base of the prostate into and around the seminal vesicle Focal or diffuse low T2WI signal intensity Abnormal contrast enhan
13、cement within and/or along the seminal vesicle Restricted diffusion,obliteration of the angle between the base of the prostate and the seminal vesicle21Lymph node metastasis 8mm in short axis Nodal groups that should be evaluated Common femoral Obturator External iliac Internal iliac Common iliac Pa
14、rarectal Presacral Paracaval Para-aortic22Structured report of Prostate MRRID 10312 磁共振成像 Magnetic resonance imaging Magneticam resonatur imaginatione Die Magnetresonanztomographie 磁気共鳴-imagerie par rsonance magntique La resonancia magntica La risonanza magnetica23Start Here:PZ or TZ?PZTZ12354123541
15、2354By PI-RADS v2 logicRADLex ID临床评估影像所见诊断1.除外前列腺临床显著癌2.已确诊前列腺癌，拟行术前分期3.其他临床评估影像所见外周带及移行带1、4、5分信号单一2、3分信号可能性多默认信号，可自行修改1-2分：整体描述3-5分：病灶描述影像所见诊断1.除外前列腺临床显著癌2.已确诊前列腺癌，拟行术前分期Management of prostate cancer based on mpMRIRecent articles reporting the role of mpMRI in prostate biopsyRecent studies of the r
16、ole of mpMRI in determining active surveillance eligibilityRecent studies of the role of mpMRI in high-risk prostate cancerRecent studies of the role of mpMRI in detecting local recurrence after radical prostatectomyLiterature NICE Guidelines,UK 2014 ESUR/ACR Guidelines 2012/2014 Vache T et al,Radio
17、logy 2014 de Rooij M et al.AJR 2014 Willis SR et al BMJ Open 201435 mpMRI has performance characteristics to help manage patients with suspected or proven prostate cancers Ability to“rule in”and“rule out”disease depends on the mpMRI approach,image quality,reading system&reporter expertise Cancer det
18、ection ability is dependent on the anatomic location,tumor volume and aggressiveness mpMRI detected lesions are not always malignant;biopsy is always needed.Rule out rule in performance!Clinical utility of mpMRI is an interdependent function between target disease prevalence&test performance36What i
19、s the MRI target?“clinically significant cancer”A tumor that poses a significant risk to health depends on Aggressiveness of the tumor Life expectancy(period of risk)Definition debated:often used Index tumor volume 0.5 ml and/or Gleason pattern 4 or 5 and/or Extra-capsular disease(ECE/SVI)37Signific
20、antinsignificant38Each component of mpMRI is helpful fordetecting clinically significant cancer39Sequences FunctionT2WI(&T1WI)Anatomy,tissue density,gland formation,fibrosisDWIExtent of gland formation,cellular density,necrosis and perfusion.Correlates with volume&grade.MRSMembrane turnover/energeti
21、cs and replacement of normal glandular tissues.Correlates with volume&grade.DCEBlood flow and vascular permeability.May correlate with grade.Targted biopsy/RxMR guided and/or directedSuspicionKnown cancerRisk categoryUnknownLowIntermediateHighPathologicstatus-Abnormal PSA&normal DRE;-Abnormal DRE&no
22、rmal PSA;-Persistently raised PSA and 1negative TRUS biopsyPSA 20 ng/mL,orGleason score 810,orclinical stage T2cProblems ofcategorization50%have cancer dependingon above group;substantialproportion having significantdiseaseProstatectomy data suggestsa substantial proportionhave higher grade disease(
23、miss-classified)Heterogeneous group with awide incidence of biochemicalrelapse&numerous curativetherapy optionsLocal staging accuracyDetection of metastaticdisease4041SuspicionKnown cancerRisk categoryUnknownLowIntermediateHighRole of MRI inmanagementTo identify location ofsuspicious clinically sign
24、ificantlesion(s)to enableappropriately directed biopsy-To confirm truly low riskdisease so as to allow activesurveillance to be undertaken-To identify location of non-low risk disease to enablerepeat biopsy&Rx-Stage cancers to enable curative surgery with nerve sparing-If initial AS is considered,th
25、en it is important not to underestimate tumor grade/volume/stage-For EBRT,the presence ofunfavorable disease affectsduration of adjuvanthormonal Rx-For focal therapy,indexlesion localization is needed-For surgery,accurate stagingto enable curative treatmentwith negative margins&nerve sparing if poss
26、ible-To detect extensiveECE/SVI that wouldpreclude radical surgerywith negative margins-To detect nodal andbone metastases42SuspicionKnown cancerRisk categoryUnknownLowIntermediateHighType of MRILesion detection&localization with T2WI,DWI DCE-MRI-Lesion detection&localization with DWIand DCE-MRI-MRS
27、I for low ADC lesions to assess aggressiveness-Staging with high specificityECE/SVI criteria-Lesion detection&localization with DWI andDCE-MRI-MRSI for low ADC lesions to assess aggressiveness-Staging with multi-planar T2WI,DWI DCE-MRI for ECE/SVI-Accurate local stagingand pelvic nodalassessments-Bo
28、ne scan+CT abdomenor WB-MRIKey questions on performance formpMRI/PI-RADS in suspected cancer 1.Ability of mpMRI for detecting(rule in)clinically significant disease&thereby directing appropriate patient management 2.NPV of mpMRI for ruling out clinically significant disease thus enabling avoidance o
29、f biopsy&thereby reduce over-diagnosis43Assessing the literature about the utility of mpMRI to rule“in”or“out”disease mpMRI method for data acquisition and analysis should be clearly defined(acceptable)Definition of clinically significant disease should be clear Prevalence of cancer&significant canc
30、er should match what is expected in daily practice Standard of reference should reliably inform on true pathologic status(particularly NPV),short of a prostatectomy(100%prevalence!);i.e.,adequate biopsy core sampling;the more cores,the better Patient/whole prostate level analysis PPV&NPV more import
31、ant than test“accuracy”statistics44Accuracy of mpMRI for prostatecancer detection:meta-analysis45de Rooij M,et al.Accuracy of multiparametric MRI for prostate cancer detection:a meta-analysis.AJRAm J Roentgenol.2014;202(2):343-51.46The best study on the utility of mpMRI torule“in”or“out”disease 347
32、patients 177 1st biopsy 170 previous negative TRUS biopsy PSA 9.8 ng/mL(10.5-104);prostate volume 48.7 mL(9-180)Prebiopsy mpMRI 3T,No ERC,T2W/DWI/DCE,2 readersconsensus47Kuru TH,et al.Critical evaluation of magnetic resonance imaging targeted,transrectal ultrasound guidedtransperineal fusion biopsy
33、for detection of prostate cancer.J Urol 2013;190:1380-1386The best study on the utility of mpMRI torule“in”or“out”disease mpMRI assessments(3 scale)-not PI-RADS No suspicious lesions(n=94)Intermediate(n=149)Suspicious(n=104)Transperineal;US guided saturation biopsies(median 24(12-36)targeted MRI/US
34、fusion biopsy(median 4(2-6)Patient level analysis on ability to detect significant cancers(NCCN criteria)48Kuru TH,et al.Critical evaluation of magnetic resonance imaging targeted,transrectal ultrasound guidedtransperineal fusion biopsy for detection of prostate cancer.J Urol 2013;190:1380-1386“Rule
35、 in”disease ability Cancer prevalence 200 of 347 men(58%)147(42%)clinically significant 53 low risk49No suspicious group (n=94)cancer in 14(15%);11 significantIntermediate group(n=149)cancer in 100(67%);70 significantSuspicious group(n=104)cancer in 86(83%);66 significant50Implication:40%of times th
36、is patient may NOT have clinically significant disease(NCCN criteria)5180 yr,Gleason 3+3;30%cores RT and 10%cores LT.On AS 3 yrs.PSA rising from 5 to 13 ng/mlImplication:12%of times this patient may have clinically significant disease(NCCN criteria)52PSA 5.3ng/ml;TRUS-small foci of Gleason 3+3 plus
37、prostatitis in PZ;for active surveillanceFollow 1yr,post antibiotics53PSA 5.9ng/ml;enlarging anterior gland tumor with decreased enhancement in PZ.Needs targeted biopsy of the anterior TZ mass.Multiparametric MRI followed by targeted prostate biopsy for men with suspected prostate cancer:a clinical
38、decision analysis54Multiparametric MRI followed by targeted prostate biopsy for men with suspected prostate cancer:a clinical decision analysis.BMJ Open.2014 Jun 15;4(6):e004895.55Subjects at risk(variable prevalence of significant disease)Persistent suspicion:saturation and/or full template BxSyste
39、matic TRUS biopsyClinical follow-upTherapy-ve-ve+ve+veProportion of patients in different groups depends on prevalence of target condition,and specificity and accuracy of biopsy methodsCurrent management pathway for investigating patients with suspected cancer does NOT incorporate mpMRIPI-RADS 1-356
40、Subjects at risk(variable prevalence of significant disease)Diagnostic mPMRISaturation and/or full template BxSystematic TRUS targeted Bx for allClinical follow-upTherapy-ve-ve+ve+vePI-RADS 4-5-ve-Greater precision of determining tumor grade&volume(risk stratification)-Potential increased rates of d
41、etection of significant diseaseProposed pathway incorporating mpMRI for suspected cancer(most conservative)PI-RADS 357Subjects at risk(variable prevalence of significant disease)Diagnostic mPMRISaturation and/or full template BxSystematic TRUS targeted Bx for PI-RADS 3-5Clinical follow-upTherapy-ve-
42、ve+ve+vePI-RADS 4-5-veAlternate pathway incorporating mpMRI for suspected cancer(next most conservative)-Greater precision of determining tumor grade&volume(risk stratification)-Potential increased rates of detection of significant disease-Potential reduction in diagnosis of indolent disease(reduces
43、 over-diagnosis&over treatment-Reduce number of patients undergoing biopsyPI-RADS 1-2PI-RADS 3-5PI-RADS 3:Systematic TRUS targeted Bx PI-RADS 4-5:targeted Bx onlyPI-RADS 358Subjects at risk(variable prevalence of significant disease)Diagnostic mPMRISaturation and/or full template BxClinical follow-u
44、pTherapy-ve-ve+ve+vePI-RADS 4-5-veAlternate pathway incorporating mpMRI for suspected cancer(least conservative)-Greater precision of determining tumor grade&volume(risk stratification)-Potential increased rates of detection of significant disease-Potential reduction in diagnosis of indolent disease
45、(reduces over-diagnosis&over treatment-Reduce number of patients undergoing biopsyPI-RADS 1-2PI-RADS 3-5Milestone drug for CRPC59N Engl J Med.2015,373:1697-1708Clinical applications of prostate MRILocoregional stagingPast indication of MRClinical applications of prostate MRILocoregional stagingIniti
46、al diagnosisTumor detectionLocalization CharacterizationRisk stratificationLocoregional stagingGuide for biopsySurveillanceGuide for surgery,focal therapy and radiation therapyAssessment of suspected recurrencePast indication of MRPresent indication of MRClinical applications of prostate MRILocoregi
47、onal stagingInitial diagnosisTumor detectionLocalization CharacterizationRisk stratificationLocoregional stagingGuide for biopsySurveillanceGuide for surgery,focal therapy and radiation therapyAssessment of suspected recurrencePast indication of MRPresent indication of MRAssessment of targeted biops
48、yConclusionmpMRI assists in lesion detection,characterization,staging&therapy planning Potential to direct management of prostate patients63Suspected cancer mpMRI is more able to visualise clinically significant disease but will miss some significant diseaseLow risk cancer mpMRI can increase the pre
49、cision of patient selection at initial triage for ASIntermediate risk disease identifies unfavourable sub-groups&can potentially guide management on per patient basis-mpMRI interpretation needs to be aligned with local clinical management plans-Few studies show improved clinical outcomes using mpMRI&more clinical impact research is needed
