Application Value Of Multi-parametric Magnetic Resonance Imaging In The Differential Diagnosis Of HER-2 Positive And Negative Breast Cancer

Objective:To investigate the value of multi-parameter magnetic resonance imaging in the differential diagnosis of human epidermal growth factor receptor 2(HER-2)positive breast cancer and HER-2 negative breast cancer,and to provide important imaging information for formulating reasonable individualized treatment plan and evaluating the prognosis of patients.Methods:A total of 93 women with histopathology-confirmed breast cancers were retrospectively analyzed,who underwent breast magnetic resonance imaging two weeks before operation in Jining First People’s Hospital from October 2018 to February 2020,including 50 HER-2positive breast cancer and 43 HER-2 negative breast cancer.All patients underwent breast MRI plain scan,diffusion weighted imaging(DWI),diffusion kurtosis imaging(DKI)and dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI)on the same MRI machine before operation.All patients had complete postoperative immunohistochemical staining results.The morphological characteristics of the lesion and the values of apparent diffusion coefficient(ADC),mean diffusivity(MD),mean kurtosis(MK),initial enhancement rate(IER),percentage of peak enhancement(Epeak),time to peak(TTP),Wash in rate(Wash-in),Wash out rate(Wash-out),and the types of time intensity curve(TIC)of the region of interest(ROI)were recorded by two radiologists.Quantitative variables and ordinal variables between HER-2 positive breast cancer and HER-2 negative breast cancer were compared by Mann-Whitney U test or independent sample t-test,while qualitative variables were compared byx~2test or Fisher exact test.The comparison of multiple parameters between HER-2 overexpression group and Luminal B(HER2-positive)group was performed by Mann-Whitney U test or independent sample t-test.The receiver operator characteristic curve(ROC)was used to analyze and compare the diagnostic performances of DWI,DKI and DCE parameters in the diagnosis of HER-2 positive breast cancer.All statistical analysis,P<0.05 was remarkably significant.Results:There were no important differences in age,menstrual status,lymph node metastasis,Ki-67 and P53 expression between HER-2 positive and negative breast cancer(P>0.05),Pathological grade had statistical difference between two groups(P=0.032).HER-2 positive breast cancers were usually segmental or irregular lesions with burrs or irregular margins,while HER-2 negative breast cancers were mainly round or irregular lesions with smooth or irregular margins,P=0.031,P=0.033.The enhancement pattern and time-intensity curve type had no difference between HER-2 positive and negative breast cancer(P=0.209,P=0.156).The ADC value,MD value,MK value and IER value of HER-2positive breast cancer were higher than those of HER-2 negative breast cancer(P<0.05).TTP value of HER-2 positive breast cancer was lower than that of HER-2 negative breast cancer(P<0.05).The AUC(0.691)of TTP value in the diagnosis of HER-2 positive breast cancer was higher than that of ADC value,MD value,MK value,and IER value(0.65,0.64,0.67,0.67),but the differences were not statistically significant.The diagnostic efficacy of DCE combined with DWI was similar to DCE combined with DKI,with no statistically significant difference.Compared with single parameter or multi-parameter,the AUC(0.825)of DWI+DKI+DCE was the highest in diagnosing HER-2 positive breast cancer.Compared with Luminal B(HER2-positive)type(ER and or PR positive,HER2-positive),higher ADC value,MD value,SIslope value,and lower MK value were showed in the HER-2 overexpression breast cancer(P<0.05).Conclusion:The main MRI features of HER-2 positive breast cancer are segmental or irregular lesions with burrs or irregular margins,and the pathological grades were mostly grade II or grade III.The parameters ADC value derived from the DWI model,MD and MK values derived from the DKI model,and semi-quantitative parameters IER and TTP values of DCE-MRI can be used for the differential diagnosis of HER-2 positive breast cancer.By combining ADC,MD,MK,TTP,and IER values,the diagnostic efficiency was improved.The HER-2 overexpression group showed higher ADC and MD values,lower MK value than Luminal B(HER2-positive)group,suggesting that ADC,MD,and MK values have potential diagnostic efficiency in differentiating HER-2 overexpression and Luminal B(HER2-positive)breast cancer.