The Value Of Magnetic Resonance Imaging In Evaluating The Efficacy Of Neoadjuvant Chemotherapy For Breast Cancer

Objective:This study aimed to evaluate the value of magnetic resonance multiparametric imaging in evaluating the efficacy of neoadjuvant chemotherapy in breast cancer.Materials and methods:A retrospective analysis was made on 74 patients with breast cancer who received neoadjuvant chemotherapy in the second Hospital of Shandong University from May 2020 to October 2021.All patients were examined by Bard needle biopsy and the results were invasive breast cancer.All patients received 4-6 cycles of neoadjuvant chemotherapy and surgical resection after chemotherapy,and routine pathology was performed after operation.According to the Miller&Payne(MP)pathological grading system,74 patients with breast cancer were divided into two groups:Major Histological Response(MHR)and Non-Majorhistological Response(NMHR).According to the results of immunohistochemistry,the patients were divided into four molecular subtypes:Luminal A type,Luminal B type,HER-2 overexpression type and TNBC type.Before and after neoadjuvant chemotherapy,all patients need to undergo magnetic resonance examination,measure the maximum diameter of the tumor,outline the region of interest(ROI),measure the ADC value,draw the time-signal intensity curve(TIC),analyze the shape of TIC,and calculate the peak heigh(PH)and early enhancement rate(EER).The maximum tumor diameter,ADC value,PH and EER before and after NAC were compared in MHR group and NMHR group,and the above parameters were compared between the two groups before and after NAC,and the change rates of parameters between the two groups before and after NAC were calculated and compared.The measurement data were expressed by mean ±standard deviation,T test was used when obeying normal distribution,otherwise rank sum test was used,the counting data was expressed by frequency or rate,chi-square test and nonparametric test were used for comparison,and the diagnostic effects of different parameters were analyzed by ROC curve.It was statistically significant when p<0.05.Results:1.There was no significant difference in tumor maximum diameter,ADC value,EER and PH between MHR group and NMHR group before NAC.2.There were significant differences in tumor maximum diameter,ADC value,PH and EER before and after NAC in MHR group;There was no significant difference in ADC value,PH and EER in NMHR group before and after NAC,but there was significant difference in tumor maximum diameter before and after NAC.3.After NAC4-6 cycle,there were significant differences in tumor maximum diameter,ADC value,EER and PH between MHR group and NMHR group.According to ROC curve,the diagnostic efficacy of ADC value was the best.4.After NAC4-6 cycle,there were significant differences in tumor maximum diameter change rate,ADC value change rate,EER change rate and PH change rate between MHR group and NMHR group compared with those before chemotherapy.According to ROC curve,the diagnostic efficiency of ADC value change rate was the best.5.After NAC4-6 cycle,the type of TIC curve type Ⅲ curve decreased,mainly type Ⅰ and Ⅱ,type Ⅲ-Ⅰtransformation was more common in MHR group,and NMHR group did not convert more.There was significant difference in the change of TIC curve type between the two groups before chemotherapy.6.After NAC4-6 cycle,the pathological response of NAC was the best in TNBC breast cancer,followed by HER-2 overexpression and Luminal B,and the worst in Luminal A.the difference of ADC value and its change rate before and after chemotherapy between MHR group and NMHR group was only statistically significant in Luminal B type.Conclusion:1.MRI multiparameter imaging after neoadjuvant chemotherapy has certain application value in the evaluation of pathological reaction.2.ADC value and its change rate after neoadjuvant chemotherapy have high diagnostic efficacy in evaluating pathological reaction.3.MRI has high clinical value in evaluating the efficacy of various molecular subtypes of breast cancer in Luminal B breast cancer.