The Value Of Multimodal MRI In Discrimination Benign And Malignant Breast Tumors

Objective:To investigate the diagnostic value of dynamic contrast-enhanced MRI（DCE–MRI）and intravoxel incoherent motion（IVIM）imaging in benign and malignant mammary tumors.Materials and Methods:The preoperative mammary DCE-MRI and IVIM imaging data of 76 patients with breast tumor admitted to the First People’s Hospital of Kashgar from January 2018 to August 2020 were analyzed retrospectively,relevant parameters,including time intensity curve（TIC）,IVIM sequence of diffusion coefficient of pure water molecules（D）,perfusion-related diffusion coefficient（D*）and perfusion fraction（f）were calculated,and the pathological results were taken as gold standard,to make a comprehensive analysis of the differences between benign and malignant mammary tumors in the above parameters and probe into the diagnostic performance of two magnetic resonance imaging methods severally and jointly.Results:The results of statistical analysis indicated that the TIC curves of benign tumors were mostly inflow type,while the TIC curves of malignant tumors were mostly plateau type or outflow type（P<0.05）.For TIC curves,the diagnostic sensitivity was 92.2%,the specificity was 69.4%and the receiver operating characteristic curve,area under curve（ROC AUC）was 0.836,with P<0.05 standing for statistically significant difference.The mean D value of benign tumor was 1.31±0.24×10^-3mm²/s,the mean D value of malignant tumor was0.93±0.21×10^-3mm²/s,the D value in the benign group was higher than that in the malignant group（P<0.05）.For D value,the diagnostic sensitivity was 94.3%,the specificity was 86.1%,the ROC AUC was 0.960,and the optimal threshold was 1.075×10^-3mm²/s,with P<0.05 standing for statistically significant difference.The mean f value in the malignant group was 10.15±5.85%,the mean f value in the benign group was 7.36±5.25%,and the f value in the malignant group was higher than that in the benign group（P<0.05）.For f value,the diagnostic sensitivity was 82.5%,the specificity was 72.2%,the ROC AUC was 0.829,and the optimal threshold was8.65%.Besides,there were no statistically significant differences between benign and malignant tumor groups in D*value.Further results indicated that the diagnostic sensitivity of joint IVIM and DCE-TIC was 97.5%,the specificity was 99.4%and ROC AUC was 0.963.The diagnostic sensitivity of D value,f value,joint evaluation of D value and f value,in TIC plateau-type breast tumors were 90.0%,90.0%and100%,while the specificity were 75%,75%and 87.5%and the AUCs were 0.938,0.806 and 0.938 respectively.Conclusion:1.DCE and IVIM imaging play an important role in the diagnosis of benign and malignant breast lesions.2.D value,f value and other evaluation indicators have better diagnostic performance,and D value has better diagnostic sensitivity and specificity than F value.3.The combination of DCE-TIC curve,D value,f value and other evaluation indicators has a higher diagnostic performance than that of the two methods severally.4.In view of the large overlap between DCE-TIC plateau-type benign and malignant breast tumors,the application of IVIM can help further identify the benignity and malignancy of DCE-TIC plateau-type breast tumors.