Evaluation of pathologic response of breast cancer to neoadjuvant chemotherapy with magnetic resonance diffusion weighted imaging / 生物医学工程学杂志

This paper aims to investigate the value of diffusiion weighted imaging (DWI) and different apparent diffusion coefficient (ADC) methods to predict the curative effects of neoadjuvant chempotherapy (NAC) for breast cancer. From March 2010 to December 2012, seventy-one patients were pathologically confirmed invasive breast cancer by needle puncture biopsy received before surgery, and underwent magnetic resonance before and after NAC, the ADC were measured by mean ADC method and lower ADC method. The pathologic response after NAC was divided to major histological response (MHR) group and non-major histological response (NMHR) group according to Miller & Payne system. Results displayed that ADC values obtained before NAC, at the end of the second cycle of NAC, and after whole course of treatment, had good correlations between mean and lower ADC methods (the Pearson's correlation=0.699, 0.749 and 0.895, respectively). Significant difference in ADC obtained both with mean and lower ADC methods could be found between MHR and NMHR groups after the second cycle of NAC (P< 0.05). After the second cycle of NAC, significant difference in the change rate of ADC could be found between MHR and NMHR groups by using lower ADC method (P<0.05), but not be found by using mean ADC method (P >0.05). In conclusion, DWI could monitor the pathologic changes of breast cancer after NAC, and the lower ADC method might be used to evaluate the curative effect of NAC with the change rate of ADC.

The actions of diffusion weighted imaging (DWI) and dynamic contrast enhanced MRI in differentiating breast tumors / 生物医学工程学杂志

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.