A comparative study of the value of amide proton transfer-weighted imaging and diffusion kurtosis imaging in the diagnosis and evaluation of breast cancer

Objectives: To compare the value of amide proton transfer-weighted imaging (APTWI) and diffusion kurtosis imaging (DKI) in differentiating benign and malignant breast lesions and analyze the correlations between the derived parameters and prognostic factors of breast cancer.

Methods: One hundred thirty-five women underwent breast APTWI and DKI. The magnetization transfer ratio asymmetry (MTRasym (3.5 ppm)), apparent kurtosis coefficient (K_app), and non-Gaussian diffusion coefficient (D_app) were calculated according to the histological subtype, grade, and prognostic factors (Ki-67, estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER-2), lymph node metastasis, and maximum lesion diameter). The differences, efficacy, and correlation between the parameters were determined.

Results: The K_app value was higher and the D_app and MTRasym (3.5 ppm) values were lower in the malignant group than in the benign group (all p < 0.001; AUC (K_app) = 0.913, AUC (D_app) = 0.910, and AUC (MTRasym (3.5 ppm)) = 0.796). The differences in the AUC between K_app and MTRasym (3.5 ppm) and between D_app and MTRasym (3.5 ppm) were significant (p = 0.023, 0.046). K_app was moderately correlated with the pathological grade (|r| = 0.724) and mildly correlated with Ki-67 and HER-2 expression (|r| = 0.454, 0.333). D_app was moderately correlated with the pathological grade (|r| = 0.648) and mildly correlated with Ki-67 expression (|r| = 0.400). MTRasym (3.5 ppm) was only mildly correlated with the pathological grade (|r| = 0.468).

Conclusion: DKI is superior to APTWI in differentiating between benign and malignant breast lesions. Each parameter is correlated with some prognostic factors to a certain extent.

Key points: • DKI and APTWI provide valuable information regarding lesion characterization. • K_app, D_app, and MTRasym (3.5 ppm) are valid parameters for the characterization of tissue microstructure. • DKI is superior to APTWI in the study of breast cancer.

Keywords: APT; Breast neoplasms; Diffusion magnetic resonance imaging.