Differential Diagnostic Value Of Three-dimensional Amide Proton Transfer-weighted Imaging In Benign And Malignant Breast Masses

Background and PurposeBreast cancer has become the most common cancer in the world.Magnetic resonance imaging(MRI)as a non-invasive,non-radiation and high soft tissue contrast imaging method,plays an important role in the diagnosis,treatment and prognosis evaluation of breast cancer.Conventional MRI sequences can reflect the macroscopic characteristics of the lesion,such as size and shape,dynamic contrast-enhanced MRI(DCE-MRI)can provide additional physiological information about tumor perfusion characteristics,and diffusion-weighted imaging(DWI)can provide information about tumor cell structure and surrounding environment.However,all commonly used breast MRI sequences have some limitations,and the reliability of relying on these sequences to diagnose lesions is still controversial,so more advanced imaging techniques are needed to provide more helpful information.Amide proton transfer-weighted imaging(APTWI)is a molecular imaging technology based on chemical exchange saturation transfer(CEST),which is sensitive to endogenous mobile proteins and peptides in tissues.Recently,preliminary studies in head and neck,thyroid,chest,cervix,ovary,prostate and rectum have found APTWI is a potential tool for tumor detection and qualitative diagnosis.However,there are few studies on APTWI in the field of breast at present.So the purpose of this study is to investigate whether 3D APTWI can be used as a non-invasive functional imaging method for differential diagnosis of benign and malignant breast masses,and compare and combine it with DCE-MRI and DWI to evaluate whether APTWI can provide supplementary diagnostic information for DCE-MRI and DWI.Materials and MethodsPatients who needed breast MRI examination in our hospital from January 2021 to October 2021 due to various breast lesions were prospectively collected.All patients underwent T1 weighted imaging(T1WI),T2 weighted imaging(T2WI),DWI,APTWI and DCE-MRI before operation and finally diagnosed by operation or puncture pathology.DCE-MRI images described the shape,edge,internal enhancement characteristics,early enhancement rate and TIC of the lesions according to the Fischer’s scoring system,and the lesions were scored and classified by BI-RADS.DWI and APTWI images were uploaded to the dedicated post-processing workstation for processing and analysis,and the apparent diffusion coefficient(ADC)value and the asymmetric magnetization transfer rate of 3.5ppm[MTRasym(3.5ppm)]were obtained,respectively.According to the final pathological diagnosis,the value of the following methods in differential diagnosis of benign and malignant breast masses was analyzed and compared:①BI-RADS classification based on the DCE-MRI Fischer’s scoring system;②The quantitative parameter ADC value based on DWI;③The quantitative parameter MTRasym(3.5ppm)based on APTWI;④Combining diagnosis of APTWI and DCE-MRI(APTWI+DCE-MRI);⑤Combining diagnosis of APTWI and DWI(APTWI+DWI).Drawing the receiver operating characteristic(ROC)curve of the above methods for differential diagnosis of benign and malignant breast masses,calculating the area under the ROC curve(AUC),determining the best critical value according to the maximum Youden index,and evaluating the corresponding sensitivity,specificity and accuracy.DeLong test was used to compare the AUC.If there were any differences,McNemar test was used to compare the sensitivity,specificity and accuracy.P<0.05 was considered that the difference was statistically significant.Results1 General clinical data and the results of DCE-MRI analysisFinally,a total of 300 patients with breast masses were included in this study.There were statistically significant differences in age,lesion shape,margin,internal enhancement characteristics,early enhancement rate and TIC between benign and malignant breast masses.There were no significant differences in amount of fibroglandular tissue,background parenchyma enhancement and lesion size between benign and malignant breast masses.The AUC of BI-RADS classification based on DCE-MRI Fischer’s scoring system for differential diagnosis of benign and malignant breast masses was 0.783,and the sensitivity,specificity and accuracy were 89.35%,67.18%and 79.67%,respectively.2 Results of DWI analysisThere was significant difference in ADC value between benign and malignant breast masses.The ADC value of the malignant group[1.11(1.03,1.21)×10-3mm2/s]was lower than the benign group[1.50(1.26,1.69)×10-3mm2/s].The AUC of DWI in differential diagnosis of benign and malignant breast masses was 0.858.Taking 1.29×10-3mm2/s as the best critical value of the ADC value,the sensitivity,specificity and accuracy of DWI in differential diagnosis of benign and malignant breast masses were 87.57%,73.28%and 81.33%,respectively.3 Results of APTWI analysisThere was significant difference in MTRasym(3.5 ppm)between benign and malignant breast masses.The MTRasym(3.5 ppm)of the malignant group[2.00(1.30,2.70)%]was lower than the benign group[3.30(2.60,3.90)%].The AUC of APTWI in differential diagnosis of benign and malignant breast masses was 0.810.Taking 2.7%as the best critical value of MTRasym(3.5 ppm),the sensitivity,specificity and accuracy of APTWI in differential diagnosis of benign and malignant breast masses were 76.92%,74.81%and 76.00%,respectively.4 Comparison and combination diagnosis of APTWI and DCE-MRIThere was no significant difference between APTWI and DCE-MRI in the differential diagnosis of benign and malignant breast masses.The AUC of APTWI+DCE-MRI in differential diagnosis of benign and malignant breast masses was 0.873,which was better than that of APTWI or DCE-MRI.The sensitivity,specificity and accuracy of APTWI+DCE-MRI in differential diagnosis of benign and malignant breast masses were 87.57%,87.02%and 87.33%respectively,and the specificity and accuracy were higher than that of DCE-MRI,the sensitivity,specificity and accuracy were higher than that of APTWI.5 Comparison and combination diagnosis of APTWI and DWIThere was no significant difference between APTWI and DWI in the differential diagnosis of benign and malignant breast masses.The AUC of APTWI+DWI in differential diagnosis of benign and malignant breast masses was 0.916,which was better than that of APTWI or DWI.The sensitivity,specificity and accuracy of APTWI+DWI in differential diagnosis of benign and malignant breast masses were 91.12%,80.92%and 86.66%respectively,and the specificity was higher than that of DWI,the sensitivity and accuracy were higher than that of APTWI.Conclusions1.APTWI is a promising non-invasive molecular imaging technology,which can be used to differentiate benign and malignant breast masses,and its diagnostic efficacy is similar to that of DCE-MRI and DWI.2.The efficacy of APTWI combining with DCE-MRI or DWI in differential diagnosis of benign and malignant breast masses is better than single method,and APTWI provides supplementary information for DCE-MRI and DWI.