简介：Objective:Todeterminethevalueofdiffusion-tensorimaging（DTI）asanadjuncttodynamiccontrastenhancedmagneticresonanceimaging（DCE-MRI）forimprovedaccuracyofdifferentialdiagnosisbetweenbreastductalcarcinomainsitu（DCIS）andinvasivebreastcarcinoma（IBC）.Methods:TheMRIdataof63patientspathologicallyconfirmedasbreastcancerwereanalyzed.TheconventionalMRIanalysismetricsincludedenhancementstyle,initialenhancementcharacteristic,maximumslopeofincrease,timetopeak,timesignalintensitycurve（TIC）pattern,andsignalintensityonFST2WI.Thevaluesofapparentdiffusioncoefficient（ADC）,directionally-averagedmeandiffusivity(Davg),exponentialattenuation（EA）,fractionalanisotropy（FA）,volumeratio（VR）andrelativeanisotropy（RA）werecalculatedandcomparedbetweenDCISandIBC.MultivariatelogisticregressionwasusedtoidentifyindependentfactorsfordistinguishingIBCandDCIS.Thediagnosticperformanceofthediagnosisequationwasevaluatedusingthereceiveroperatingcharacteristic（ROC）curve.ThediagnosticefficaciesofDCEMRI,DWIandDTIwerecomparedindependendyorcombined.Results:EAvalue,lesionenhancementstyleandTICpatternwereidentifiedasindependentfactorfordifferentialdiagnosisofIBCandDCIS.ThecombinationdiagnosisshowedhigherdiagnosticefficacythanasingleuseofDCE-MRI（P=0.02）,andtheareaofthecurvewasimprovedfrom0.84（95%CI,0.67-0.99）to0.94（95%CI,0.85-1.00）.Conclusions:QuantitativeDTImeasurementasanadjuncttoDCE-MRIcouldimprovethediagnosticperformanceofdifferentialdiagnosisbetweenDCISandIBCcomparedtoasingleuseofDCE-MRI.