The Value Of Ultrasonic Elastography In Diagnosis Of Breast Lesions

Objective1.To compare the value of Utrasonic Elastography(UE) and Doppler Ultrasonography (DU) in the differential diagnosis of breast lesions, and analysis of each advantages and limitations.2. To get the relative stiffness of lesion by measuring the strain ratio of breast lesion to the same level breast tissue. The ROC (Receiver Operator Characteristic) curve was made by the probability of malignancy according to the strain ratio. The area under the ROC curve(Az)was the judgment index used to test the clinical diagnosis value of the strain ratio. A strain ratio cutoff enabled the best distinction between benign and malignant masses, providing a new and important detection criterion for the diagnosis of benign and malignant breast lesions.Materials and MethodsFrom December 2008 to January 2010,350 female patients with 360 breast lesions confirmed by surgical pathology were examined with DU and UE.186 lesions were benign and 174 lesions were malignantHITACHI HV-900 ultrasound system with the technology of ultrasonic elastography was used in this study. The frequency of the linear array probe is from 6.5-13.0MHz. All breast lesions were performed four ultrasonic modalities before surgery including grey-scale sonography, DU and UE. Color Doppler Flow Imaing (CDFI) should show the most vessels in the lesions. The resistive index (RI) was calculated and recorded. The UE imaging and strain ratio imaging must include lesion with no less than three views, and the normal breast glandular tissue should be displayed as green as well as the fat tissue appears as red in the imaging. All pictures saved into the hard disc. The grading of the blood flow in lesions referred to Adler half quantity method, and the elastogram were analyzed according to the five-score, which was collacted before the pathology conformed. The strain ratio should take up by caculating the average of three times.Results1. The sensitivity, specificity, accuracy, positive predictive value, negative predictive value of CDFI were 61.5%,65.2%,68.6%,69.9%, 67.6%, respectively.2. The sensitivity, specificity, accuracy, positive predictive value, negative predictive value of Spectral Doppler (SD) according to blood flow resistance index (RI) were 68.9%,79.5%,72.8%,76.4%,73.3%, respectively.3. The sensitivity, specificity, accuracy, positive predictive value, negative predictive value of UE scoring method were 83.9%,88.7%, 84.4%,87.6%,86.8%, respectively. 4. The specificity, sensitivity and accuracy of UE scoring method were all significantly higher than those of CDFI and SD compared by the McNemar x2 test(P<0.001). The positive predictive value index of UE were higher than those of CDFI and SD, respectively.5. With pathologic diagnosis as the gold standard, ROC curves were obtained to assess the performance of the strain ratio. The Az was 0.933. The strain ratio is a good method for differentiating malignant and benign breast lesions6.3.8 was the best cutoff point of the strain ratio for differentiating malignant from benign breast lesions. its senstivity, specificity, accuracy, positive predictive value and negative predictive value were 87.6%, 89.8%,88.7%,88.7%,88.6%, respectively.7. The specificity, sensitivity and accuracy of strain ratio were not significantly different with those of UE scoring method for differentiating malignant and benign breast lesions.Conclusion1. The UE are very useful in differentiating between malignant and benign breast masses. Its specificity and sensitivity were both significantly higher than those of CDFI and SD, which imply less misdiagnosis and more confidently in the diagnosis of breast lesions.2. The strain ratio of lesion to the same level breast tissue can quantitaively evaluate the stiffness of breast lesions, which is more objective than the UE scoring method. The strain ratio can be used as a new supplementary measure for differentiation of benign and malignant breast lesions. The rate of early detecting breast cancer will be improved greatly, furthermore, the number of unnecessary biopsy could be largely reduced. 3.8 was the best cutoff point of the strain ratio for differentiating malignant and benign breast lesions.