Naier LIN MS, Presenter: Nothing to Disclose

Jia Hua, Abstract Co-Author: Nothing to Disclose

To compare mono-exponential model DWI and intravoxel incoherent motion(IVIM) DWI  in characterizing different subtype and different grade of breast lesions.

51 malignant and 47 benign breast lesions in 93 patients were performed with mono-exponential DWI(b =0,600s/mm2) and bi-exponential analysisDWI (b =0,50,100,150,200,500,800 s/mm2) at 3.0T MRI. Apparent diffusion coefficient (ADC), as well as IVIM-based parameters:true diffusion coefficient (D), perfusion fraction (f), and pseudo-diffusion coefficient (D*)  were compared among different subtype and different grade lesions . Receiver operating characteristic (ROC) was used for lesion discrimination.

All the data were fitted well (R2>0.90). In the lesions except cyst, D value was significant lower than ADC (p<0.05).ADC, D and D* in malignant tumors were significantly smaller than those of benign ones (P = 0.000 for ADC and D ,0.002 for D*, respectively), f value was higher than that of benign lesions (P=0.000). D  value showed increasing order as the following: Invasive ductal carcinoma (IDC)< ductal carcinoma in situ (DCIS) ≈Intraductal papilloma (IDP) <Fibroadenoma (FA)< breast cyst. ROC demonstrated D had the best performance in identification of malignancy from benign lesion (AUC= 0.945) and discriminating DCIS from IDC (AUC= 0.791) than that of ADC,f and D*. Furthermore,a direct inverse correlation had been observed between D value and histological IDC grade,while no other parematrers showed difference among varied grade of IDC (P>0.05).

IVIM-DWI provides quantitative measurement of cellularity and vascularity properties within breast lesions and D showed better diagnostic ability in discrimination malignancy and tumor grading than ADC. therefore IVIM are expected to enhance the role of MRI in diagnosis, monitoring, and treatment screening of breast cancer.

IVIM provides noninvasive sensitivity to lesions microenvironment properties and has the potential to improve the specificity of breast MRI without contrast agent ,thus it is recommended as part of the  MR  exam for screening  high-risk women.

LIN, N, Hua, J, Intravoxel Incoherent Motion MR Imaging at 3.0T in Breast: Quantitative Analysis for Characterizing Breast Lesions.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14000317.html