Diagnostic Value Of Cominging Dynamic Contrast Enhanced MR Imaging, Diffusion Weighted Imaging For Diagnosis Of Breart Tumour

Objective: To analyze the sensitivity , specificity and accuracy ,positive predictive value and negative predictive value of dynamic contrast enhanced imaging , diffusion-weighted imaging and combination of the two methods for the diagnosis of breast lesion , and to evaluate their diagnostic validity.Methods: Forty senen lesions from 42 patients were acquired with histopathological demonstration , include 21 malignant cases ( 23 lesions)and 21 benign cases(24 lesions). All lesions were examined with dynamic contrast enhanced MRI and DWI. The images were reviewed by two radiologists at Synogo workstation and made consensus on the type of time signal intensity curve (TIC) . The lesions were classified as malignant , suspicious or benign according the score summed up. Apparent diffusion coefficient (ADC) of the lesion was acquired using region of interest (ROI) technique correlated with the location of enhanced lesion by software on the workstation. The same size ROLwas selected on the other breast in same slice.T test statistical method used to compare ADC and rADC, and lesions were classified as benign and malignant. The ADC and rADC values of all breast lesions were calculated and its threshold of differentiating benign or malignant lesions were affirmed with receiver operating characteristic curve (ROC) ,area under ROC were calculated as well. Through comparation , to determine the best diagnostic indicators.The validities of time intensity cure (TIC) , ADC , and combination of the two methods were evaluated.Results: The sensitivity , specificity and accuracy , positive predictive value and negative predictive value of dynamic contrast enhanced imaging were 95.7%(22/23),75.0%(18/24),85.1%(40/47),78.6%(22/28),94.7%(18/19). The benign lesion group ADC was 1.414±0.395 (×10 -3mm~2 / s) , and the malignant group was 0.932±0.202 (×10 -3mm~2 / s) . To the total numbers had significant difference ( P < 0. 05) . In the study the rADC was used to try to Partially eliminate the varinaces among dieffrent in dividuals . By analysising ADC and relative ADC of ROC curve , the area under the curve (Az value) were 0.884 and 0.833. By comparing the area under the ROC curve, ADC of the diagnostic performance is slightly better than the relative ADC . Therefore, we select ADC values in this study for diagnosis. The threshold between benign and malignant lesions were 1.243×10 -3 mm~2 /s and 0.533 by the method of Youden index maximum. The sensitivity , specificity ,accuracy ,positive predictive value and negative predictive value of ADC were 91.3%(21/23),75%(18/24),83%(39/47),77.8%(21/27),90.0%(18/20). To contrast ,Absolute ADC revealed slight better aeeuracy than rADC.The combination of dynamic contrast enhanced MRI and DWI ADC of breast lesions had a sensitivity , specificity, accuracy , positive predictive value and negative predictive value of of 86.9%(20/23),95.8%(23/24),91.5%(43/47),95.2%(20/21),88.5%(23/26)。 Conclusion:1,DCE一MRI is the most essential mehtod in the MR imaging of breast,but has a lower specificity.2,The differentiation of benign from malignant breast lesions by DWI and ADC is applicable.3,The combination of dynamic contrast-enhanced MRI and DWI was more diagnostic validity than only the other diagnosis examination in specificity and degree of accuracy , positive predictive value and reduce the number of unneeessary biopsies.