Comparative Study of Amide Proton Transfer-Weighted Imaging and Intravoxel Incoherent Motion Imaging in Breast Cancer Diagnosis and Evaluation.

ABSTRACT

BACKGROUND: Amide proton transfer-weighted imaging (APTWI) and intravoxel incoherent motion imaging (IVIM) are valuable MRI techniques applied to cancer. PURPOSE: To compare APTWI and IVIM in the diagnosis of benign and malignant breast lesions and to evaluate the correlations between different parameters (MTRasym [3.5 ppm], D, D*, and f) and prognostic factors for breast cancer. STUDY TYPE Retrospective. POPULATION In all, 123 breast lesions were studied before treatment, including 58 benign lesions and 65 malignant lesions. FIELD STRENGTH/SEQUENCE Conventional MRI (T1 WI, T2 WI, and diffusion-weighted imaging [DWI]), APTWI, and IVIM MRI at 3T. ASSESSMENT The magnetization transfer ratio asymmetry at 3.5 ppm (MTRasym [3.5 ppm]), diffusion coefficient (D), pseudo diffusion coefficient (D*), and perfusion fraction (f) values were compared between the benign and malignant groups and between groups with different expression levels of prognostic factors. STATISTICAL TESTS Individual sample t-test, χ2 test, Spearman correlation, logistic regression, and the Delong test. RESULTS: The D and MTRasym (3.5 ppm) values of the malignant group were lower than those of the benign group; however, D* and f values were higher than those of the benign group (all P < 0.05). The areas under the curve (AUCs) of D, MTRasym (3.5 ppm), D*, and f were 0.809, 0.778, 0.670, and 0.766, respectively; however, only the difference between AUC (D) and AUC (D*) was significant (Z = 2.374, P < 0.05). The D value showed a low correlation with the pathological grade and Ki-67 expression (| r | = 0.294, 0.367); the f value showed a low correlation with estrogen receptor (ER) expression (| r | = 0.382); and the MTRasym (3.5 ppm) value showed a low correlation with pathological grade (| r | = 0.371). DATA CONCLUSION: This analysis revealed that both IVIM and APTWI could be used for the differential diagnosis of benign and malignant breast lesions, and APTWI-derived MTRasym (3.5 ppm), IVIM-derived D, D*, and f values showed correlations with some prognostic factors for breast cancer. LEVEL OF EVIDENCE 2 TECHNICAL EFFICACY STAGE 2 J. Magn. Reson. Imaging 2020;521175-1186.