The Value Of “Lotus Root Sign” On Coronal Plane Of Automatic Breast Volume Imaging Scanner(ABVS) In The Diagnosis Of Breast Lesions

ObjectivesThe purpose of this study is to analyze the sonographic features of Automated Breast Volume Scanner(ABVS)in 243 breast lesions retrospectively,explore the clinical application value of“Lotus root sign”and its imaging mechanism;analyze the correlation between “Lotus root sign”and molecular biological factors of breast cancer;compare the diagnostic efficacy of ABVS with Magnetic Resonance Imaging(MRI)in breast tumors and explore the features of TIC in breast cancer with“Lotus root sign”on the coronary plane of ABVS.MethodsThis study prospectively evaluated 198 patients with 243 lesions(112 on the left,131 on the right)which were examined in the third affiliated hospital of Guangzhou Medical University from January 2016 to December 2019.All patients underwent ABVS and all breast lesions were histopathologically confirmed.The“Lotus root sign”is a ultrasonic sign found in malignant lesions of this group which means some round or oval more hypoechoic echo areas in the interior zone of these hypoechoic lesions.First of all,the diagnostic efficiency of “Lotus root sign” was analyzed using histopathological examination as the gold standard,then the imaging mechanism of “Lotus root sign”was explored,Secondly,according to the pathological results of breast lesions,not only the correlation between “Lotus root sign” and molecular biological factors of breast cancer was anlysed,but also the distribution of “Lotus root sign”in different molecular types of breast cancer.Finally,compared the sensitivity,specificity,Positive predictive value(PPV),Negative predictive value(PPV)and accuracy of ABVS and Magnetic Resonance Imaging(MRI)in this group.Results1 Among the 243 breast lesions were studied,there were 101 malignant lesions(51 on the left,50 on the right)and 142 benign lesions(61 on the left,81 on the right),the malignant group included 75 cases of invasive ductal carcinoma of non special type(IDC),15 cases of ductal carcinoma in situ(DCIS),2 cases of pure mucinous carcinoma,1 case of squamous cell carcinoma,7 cases of solid intraductal papillary carcinoma and 1 case of diffuse large B-cell lymphoma;the benign group included 60 cases of fibroadenoma,8 cases of adenosis,19 cases of intraductal papilloma,11 cases of mammitis,28 cases of cyclomastopathy,1 case of fat necrosis,1 case of tubular adenoma,10 cases of cystic changes and 4 cases of benign phyllodes tumours;2 There were 111 lesions with the“Lotus Root Sign”on the coronal plane of ABVS,among them,81(80.2%)were malignant and 30(21.1%)were benign.The difference of“Lotus Root Sign”in benign and malignant breast lesions was statistically significant.(P<0.001).“Lotus Root Sign” had a high sensitivity for the diagnosis of breast malignant lesions(81.2%);3 The diagnosis of“Lotus Root Sign”was consistent with the pathological results(Kappa = 0.566,Sig = 0.000).The sensitivity,specificity,accuracy,PPV and NPV of “Lotus Root Sign” and “Convergence sign” were 81.2% vs.28.7%,78.9% vs.96.5%,73.2% vs.85.3%,79.4% vs.65.6%,79.8% vs.68.3% respectively;4 The imaging mechanism of "lotus root sign" may be related to the ratio of cells and interstitium in the tumor.When the proportion of tumor stromal cells in breast cancer is high and diffusely distributed,the "lotus root sign" may appear in the coronary plane of ABVS.When the internal components of the breast ducts changed from various factors,ducts with different degrees of expansion can also be manifested as a "lotus root sign";5 The occurrence ratio of the “Lotus Root Sign” among the lesions with different maximum diameter groups(P = 0.154)was not statistically significant;the occurrence ratio of the “Lotus Root Sign” in the HER-2 positive group and the negative group was not statistically significant(P = 0.377);The occurrence rate of “Lotus Root Sign” in the ER-positive group was higher than that in the ER-negative group,but the difference was not statistically significant(P = 0.834);the incidence of “Lotus Root Sign” in the PR-positive group was higher than that in the PR-negative group,but the difference was not statistically significant(P = 0.787);the occurrence rate of “Lotus Root Sign” in Ki-67 positive group was higher than that in Ki-67 negative group,but the difference was not statistically significant(P = 0.506);6 The sensitivity,specificity,accuracy,PPV and NPV of ABVS and MRI for the diagnosis of breast masses were 84.7% vs.91.5%,75.8% vs.87.9%,81.5% vs.90.2%,86.2% vs.93.1%,73.50% vs.85.3%.The area under the ROC curve of ABVS and MRI were 0.791 and 0.799(Z = 0.01,P <0.05);7 Ninety-two breast cancer lesions were underwent ABVS and MRl,34 of them were benign and 58 of them were malignant.Among 58 malignant masses,the coronal plane of 51 masses showed “Lotus Root Sign”,6(11.8%,6/51)masses got I type of curve in MRI,45(88.2%,45/51)masses showed II or III type of curve in MRI.ConclusionIn our research,the appearance of “Lotus root sign” on the coronal plane of ABVS in the group of malignant breast tumors was significantly higher than the group of benign breast tumors.The imaging mechanism of this feature may be related to the proportion of tumor stromal cells inside the tumor.Although the“Lotus root sign”in this study had no obvious correlation with the molecular biological factors of breast cancer,this sign had certain value for the differential diagnosis of benign and malignant breast tumors and can be used as a characteristic feature for the diagnose of benign and malignant breast tumors.To a certain extent,the diagnostic performance of ABVS is comparable to MRI,the “Lotus root sign” on the coronal plane of ABVS may be associated with the Ⅱ or Ⅲ type of curve in MRI.