The Value Of Multimodal Magnetic Resonance Imaging In Evaluating The Efficacy Of Neoadjuvant Chemotherapy For Breast Cancer And Its Differences In Different Molecular Subtypes

Objective To explore the value of dynamic contrast-enhanced magnetic resonance imaging and diffusion-weighted imaging in multimodal imaging in the early evaluation and prediction of the final pathological effect of breast cancer,and to analyze its differences in different molecular subtypes.Methods A total of 109 patients who diagnosed as breast cancer and operated after neoadjuvant chemotherapy in the First Affiliated Hospital of Jinzhou Medical University were retrospectively analyzed from September 2016 to December 2018.All patients had at least two complete breast DCE-MRI and DWI-MRI imaging data（before NAC,1 week after the second cycle of NAC）,measure and record the maximum diameter（D）,early enhanced rate（EER）,maximum enhanced rate（MER）,ADC value,rADC value of the lesion.And calculate the rate of change（ΔD%,ΔEER%,ΔMER%,ΔADC%,ΔrADC%） at the second cycle of NAC,respectively.Molecular typing（Luminal A,Luminal B,Her-2 overexpression and triple negative） was recorded based on preimmunization immunohistochemistry results.All enrolled patients underwent surgical treatment after NAC,and were classified into major histologically response group（MHR） and non-major histological response group（NMHR） according to postoperative Miller-Payne pathological diagnosis.The data were statistically analyzed by t test,U test and other methods,and the receiver operating characteristic（ROC） curve was further drawn to find the optimal diagnostic threshold and judge the diagnostic efficiency.Results 1.The maximum diameter of the lesion decreased after the second cycle of NAC,and there was a statistical difference between the MHR group and the NMHR group.The change rate ΔD% had higher predictions for the three subtypes except Luminal A type;2.In the semi-quantitative parameters,the EER₀ of the pre-NAC MHR group was significantly higher than that of the NMHR group,and the Luminal type breast cancer had the effect of predicting the final pathological effect;at the second cycle of NAC,EER₂ and MER₂ were both There was a statistical difference between the MHR group and the NMHR group.The reduction rates of ΔEER% and ΔMER% were predicted in all four subtypes;3.In the DWI parameters,the rADC values of Luminal B type and HER-2 overexpression type before NAC were statistically significant between the MHR group and the NMHR group,and have poor predicted efficacy.In the second cycle of NAC,the ADC value and rADC value increased.Except for Luminal A,the ADC₂ value and the ΔADC% of the MHR group and the NMHR group in the other subtypes were statistically significant,and have predictive efficacy.The rADC₂ value after NAC cycle 2 only has a predictive effect on the final pathological response to HER-2;its ΔrADC% only predicts the efficacy for the triple negative type.Conclusions 1.Multimodal magnetic resonance can be used as an effective means to predict and evaluate the efficacy of early stage of NAC,ΔD%,ΔEER% and ΔMER% of the semi-quantitative parameters of hemodynamics,the ADC₂ value and ΔADC% of the DWI parameters are prefer;while the rADC value is not recommended as an evaluation tool;2.At the second cycle of NAC,the diagnostic efficiencies of the parameters in different molecular subtypes were different.Semi-quantitative parameters were selected for Luminal A breast cancer,and clinical comprehensive evaluation of efficacy was recommended and routine follow-up;for Luminal B,HER-2 and triple negative breast cancer,ΔD%,ΔEER%,ΔMER%,ADC₂ and ΔADC % has good predictive performance.