The role of low b value diffusion-weighted MR imaging and the apparent diffusion coefficient values in diagnosis of breast tumors

Objective:To evaluate the role of low b value diffusion-weighted imaging(DWI) in detecting breast tumors.Methods:Forty-eight female patients underwent breast MRI with Philips Gyroscan-NT 1.5PT including SE-echo planar(SE-EPI),DWI and dynamic contrast-enhanced MRI.Fifty-three breast lesions were detected on DWI and the histological diagnoses were as follows:24 malignant lesions and 29 benign lesions.Twenty healthy volunteers served as the control group.Analysis of the DWI signal characteristics of the lesions and normal breast tissues and quantitative analysis and comparison of the apparent diffusion coefficient(ADC) value differences between patients and controls,benign group and malignant group were made.Results:Except for 2 cases of carcinoma in situ and 1 case with small fibroma not being shown,other benign and malignant lesions of DWI were all demonstrated.The mean ADCs of the malignant lesions were significantly lower than those of the benign lesions(P0.01) and the normal tissues(P0.01).There was no difference between the benign lesions and normal tissues.The mean ADC value of breast tumors was 1.542×10-3mm2/s according to receiver operator characteristic curve(ROC) criteria.The sensitivity and specificity of the ADC value for breast tumors were 86.4% and 89.3%.Conclusion:The ADC value is useful in differentiating malignant breast lesion from benign and normal breast tissue.Low b value DWI is an effective imaging technique for detecting breast lesions.