[The actions of diffusion weighted imaging (DWI) and dynamic contrast enhanced MRI in differentiating breast tumors]

We studied the actions of diffusion weighted imaging (DWI) and dynamic contrast enhanced (DCE) magnetic resonance imaging (MRI) in differentiating breast tumors. From January 2010 to February 2012, we retrospectively analyzed data of 95 cases with breast tumor pathologically confirmed from DWI and DCE-MRI. We compared the ADC value, time-intensity curve (TIC) and DCE-MRI parameters between breast tumors, and calculated the sensitivity and specificity for differentiating breast tumors. The results were as follows: (1) On DWI, mean ADC value of malignant tumor was lower than that of benign tumor (P < 0.05). For differentiating breast malignant tumors from benign neoplasm, a cut-off ADC value of 1.2 x 10(-3) mm2/s achieved a sensitivity of 74.1% and specificity of 70.3%. (2) On DCE-MRI, early enhancement ratio (EER) value of malignant tumor was higher than that of benign tumor whereas value of time to peak (Tpeak) and maximal enhancement ratio (SImax) were lower than that of benign tumor (all P < 0.05). As for TIC, type II and III were more frequently seen in malignant tumor than in benign tumor whereas type I was more common in benign tumor than in malignant tumor (all P < 0.05). For differentiating breast malignant tumors from benign neoplasm, DCE-MRI obtained a sensitivity of 89.7% and specificity of 70.3%. (3) For differentiating breast malignant tumors from benign neoplasm, ADC value together with TIC obtained a sensitivity of 79.3% and specificity of 78.4%. Malignant or benign breast tumors could have their own unique characteristics on DWI and DCE-MRI. These characteristics might be helpful for differentiating these tumors.