Value of Dynamic Contrast enhanced Magnetic Resonance Imaging and Diffusion Weighted Imaging in Diagnosing BI RADS Category 4 5 Breast Lesions
Purpose:The objective was to investigate the value of dynamic contrast enhanced magnetic resonance imaging(DCE MRI)and diffusion weighted imaging(DWI)in diagnosing BI RADS category 4 5 breast mass like lesions.Methods: Seventy patients with BI RADS category 4 5 breast lesions were studied by DCE MRI before histopathologic verification.The time signal intensity curves(TIC) were obtained.The imaging features were statictically analyzed with chi square test or Fisher's exact test.The apparent diffusion coefficient(ADC) values were recorded and analyzed by t test and ROC analysis.Results: Pathologic diagnoses revealed 42 malignant lesions and 27 benign ones.Significant difference was found between malignant and benign lesions on the basis of spiculated margin,rim enhancement,and TIC of rush out type for the BI RADS 4 5 lesions(P 0.05).Significant difference wasn't found between malignant and benign lesions on the basis of the lesion shapes and the early enhancement rates for the BI RADS 4 5 lesions(P 0.05).Significant difference was found between malignant and benign lesions on the basis of ADC values(t=4.903,P=0.000).The sensitivity(82.4% and specificity(80.6% were obtained with b value of 900 s/mm2 and threshold of 1.12x10 3 mm2/s.Fibroadenoma and intraductal papilloma were the usual lesions to produce false positive results.Conclusion: Conjunction of DCE MRI and DWI is helpful to improve the differential diagnosis between benign and malignant lesions,and it is useful to guide the clinical therapy.