Evaluation Of Breast Cancer Response To Neoadjuvant Chemotherapy In Different Cycles By Diffusion Weight Imaging And Dynamic Contrast Enhanced Magnetic Resonance Imaging

Objective To evaluate the therapeutic effects of neoadjuvant chemotherapy in different periods by using 3.0T diffusion weighted MRI and quantitative dynamic contrast enhancement parameters,and to understand the therapeutic effect of neoadjuvant chemotherapy at different stages of neoadjuvant chemotherapy.Method A retrospective analysis of 23 patients with breast cancer confirmed by needle biopsy from February 2017 to March 2018 in the Hospital of Chinese University affiliated to Southeast University,and All patients agreed and received complete cycles of neoadjuvant chemotherapy,and the final pathological results were obtained.DWI and DCE MRI were performed before neoadjuvant chemotherapy?after 2?4?6 cycles of the chemotherapy,and tumor size(Dimension,D)?time-intensity curve(TIC)and apparent diffusion coefficient(ADC)?Volume Transfer Constant(Ktrans)?rate constant(Kep)and Volume of extracellular space per it volume of tissue(Ve)were obtained.All the patients were divided into group major histological response(MHR)and group non-Major histological response(16 cases and 7 cases respectively)according to Miller-Payne grade.Kolmoforov-Smirnov Z test was used to verify whether the changes of ADC value,Ktrans value,Kep value and Ve value of each cycle accord with normal distribution,and the analysis of variance(ANOVA)was used to compare the variation values of each parameter in different periods(P<0.05).Histopathology was used as the gold standard to evaluate the curative effect.Logistic regression equation was used to evaluate the change rate of MRI parameters and the ability of AD%and ATIC to predict the curative effect.Results 1.After treatment of the neoadjuvant chemotherapy,the tumor was gradually shrinking and ADC value was increased while the value of Ktrans and Kep decreased,and the change value of the MHR group was more obvious than that of the NMHR group.2.Except D and Ve,the rate of change of the other parameters was statistically different during each cycles and the change rate of the parameters was the largest after the second cycle,which indicated that the reaction of tumor to chemotherapeutic drugs was the most obvious in the early stage of chemotherapy.3.There was a statistically significant difference in the changes of ADC,Ktrans and Kep after the second cycle of chemotherapy in NMHR group and MHR group,while there was no significant difference in the change value of the size of tumor.After the 4th and 6th cycles of chemotherapy,there were significant differences in the rate of change of each parameter,except the value of Ve,between NMHR group and MHR group.Conclusion The response of tumor to the treatment of neoadjuvant chemotherapy is more obvious in the early stage of chemotherapy.Magnetic resonance functional imaging parameters can predict the effect of neoadjuvant chemotherapy earlier than tumor size.