DCE-MRI Combined With DWI In Differential Diagnosis Of Different Molecular Subtypes In Massive Breast Cancer

Objective:By analyzing ADC value,dynamic enhancement curve characteristic and related parameters of different subtypes of breast cancer,and explore the differences of ADC value,dynamic enhancement and related parameters between different subtypes of breast cancer and the correlation between ADC value and prognosis of breast cancer.Methods:The patients with massive breast cancer who had been diagnosed with breast surgery at the affiliated hospital of Southwest Medical University from April 2017 to December 2017 were collected and MR plain scan and diffusion weighted imaging were performed in the radiology department of our hospital,fifty-six cases of breast cancer were included in the study,including one case of bilateral breast cancer,one case of three lesions（one small lesion of three lesions was not selected in this study）two lesions in a patient,a total of fifty-nine lesions（including fifty-two cases of non-specific type of invasive carcinoma,three cases of invasive lobular carcinoma,high-grade ductal carcinoma in situ with part of the infiltration of four）;MR examination of all cases within one week after rough Needle puncture or surgical pathology and immunohistochemistry confirmed.The ADC values of all the lesions were measured at the Philips workstation.According to the immunohistochemistry,all the lesions were classified into four subtypes(ten of which were Luminal A,twenty-nine Luminal B,Her-2 positive twelve,eight of Triple negative,and according to the character of Her-2,the twenty-nine of Luminal B was further divided into twelve of Luminal B positive and fifteen of Luminal B negative（two cases were undefined the character of Her-2）;The mean age and tumor size were compared between the four subtypes of patients.The differences of average ADC values between Luminal A,Luminal B,Her-2positive and Triple negative breast cancer were compared;Comparison of the difference of average ADC value between Luminal B positive,negative and three other molecular subtypes.According to the results of immunohistochemistry in all lesions of ER,PR,Her-2 and Ki-67 were divided into positive and negative respectively,and the average ADC values of prognostic factors between positive and negative groups were compared.The correlation between breast cancer ADC values and Ki-67 values was analyzed.The morphology,edge,the pattern of enhancement,dynamic contrast-enhanced of time signal intensity curve,early enhancement ratio of the four molecular subtypes were compared.Results:（1）One-way ANOVA was used to compare Luminal A,Luminal B,Her-2 positive,Triple negative average age and mean lesion size,there was no significant difference between the four groups（P>0.05）.（2）The average ADC values of Luminal A,Luminal B,Her-2 positive and Triple negative were（1.096±0.184）×10^-3mm²/s,（1.038±0.127）×10^-3mm²/s,（1.053±0.124）×10^-3mm²/s and（0.936±0.194）×10^-3mm²/s,respectively.The mean ADC values of four subtypes of subtypes were analyzed by ANOVA with multiple sample mean values,there was no significant difference between the two groups（P=0.153）.Further comparison between two,there was a significant difference between Luminal A and Triple negative（P=0.026）,but there was no significant difference among the other groups（P>0.05）.The average ADC values of Luminal B positive and negative were（1.096±0.142）×10^-3mm²/s,（0.992±0.101）×10^-3mm²/s,respectively.The positive and negative of Luminal B were compared with Luminal A,Her-2 positive and Triple negative,Luminal B negative and Triple negative was statistically significant（P=0.019）.There was no significant difference between other groups（P>0.05）.（3）ER positive and negative group average values of ADC were（1.030±0.133）×10^-3mm²/s,（1.047±0.175）×10^-3mm²/s,PR positive and negative group average values of ADC were（1.058±0.151）×10^-3mm²/s,（1.012±0.148）×10^-3mm²/s,Her-2 positive and negative group of average values of ADC were（1.069±0.132）×10^-3mm²/s,（1.017±0.164）×10^-3mm²/s,Ki-67 positive and negative group of average values of ADC were（1.018±0.143）×10^-3mm²/s,（1.105±0.163）×10^-3mm²/s.The mean ADC values were analyzed by independent samples t test between the positive and negative group of ER,PR,Her-2 and Ki-67.The Pearson linear correlation coefficient was used to compare the correlation between Ki-67 and ADC,showing a slight negative correlation（t=0.049,r=-0.257）.（4）Four molecular subtypes of lesion morphology:four cases of Luminal A with irregular,five with circular,one with lobular.Among Luminal B twenty cases with irregular shape,two cases with round,lobular in seven cases.There were ten cases with irregular shape of Her-2 positive,one case with round,one case with lobular.three cases with irregular of Triple negative,one case with round and four cases with lobular.Compared with Chi-Square Tests,four molecular subtypes lesions morphological differences were statistically significant（χ²=13.217,P=0.019）.（5）Four subtypes of molecular features:Among Luminal A,irregular in six,smooth margin in three,spiculated in one.Among Luminal B twenty-one with irregular,smooth margin in one,spiculated in seven.Among Her-2 positive irregular in six,smooth edge in one,spiculated in five.Triple negative irregular in two,smooth margin in one and spiculated in five.The marginal features of different molecular subtypes were compared by Chi-Square Tests with statistical significance（χ²=11.832,P=0.036）.（6）The enhancement pattern of different molecular subtypes:Luminal A mass homogeneous enhancement in two,heterogeneous enhancement in six,rim enhancement in two.Luminal B mass homogeneous enhancement in two,heterogeneous enhancement in ten,rim enhancement in seventeen.Among Her-2 positive,three with mass homogeneous enhancement,heterogeneous enhancement in eight,rim enhancement in one.Triple negative mass homogeneous enhancement in one,heterogeneous enhancement in six,rim enhancement in one.Compare by Chi-Square Tests,four molecular subtypes of lesions enhanced features were statistically significant differences（χ²=14.144,P=0.015）.（7）There is no statistical difference between the subtype time signal intensity curve and early intensification rate of different molecular subtypes（P>0.05）.Conclusion:（1）Quantitative parameters of ADC value for the prediction of different molecular subtypes of breast cancer have a certain significance.（2）The shape,edge and enhancement pattern of the massive breast cancer lesions is valuable for the identification of different molecular subtypes.（3）The MRI semi-quantitative dynamic contrast enhancement parameters have limited value in differential diagnosis of different molecular subtypes of breast cancer.