Breast Cancer Enhancement Patterns In Magnetic Resonance Imaging Before And After Neoadjuvant Chemotherapy

PurposeThe objective of this study is to analyze magnetic resonance imaging(MRI)enhancement of breast cancer before and after neoadjuvant chemotherapy(NAC)in women from a single center and to evaluate whether it can be used as a predictor of therapeutic efficacy of NAC.In addition,we want to compare the accuracy between radiologic evaluation before operation and pathological responses.MethodsWe reviewed the magnetic resonance imagings of 38 patients with LABC(locally advanced breast cancer)lesions before and after NAC.The initial enhanced lesions were classified as solitary;grouped(localized lesion with linear,spotty,or linear and spotty enhancement)and replaced lesions(diffuse contrast enhancement in whole quadrant).After NAC,the patterns of tumor shrinkage as revealed at MRI were categorized into four types.Type I(concentric shrinkage without any surrounding lesion);Type ?(concentric shrinkage with surrounding lesions);Type ?(shrinkage with residual multinodular lesions);Type ?(diffuse contrast enhancement in whole quadrant).Tumors were differently treated according to the expression of human epidermal growth factor receptor 2(HER2)based on immunohistochemical analysis and FISH tests after core needle biopsy.ResultsAmong the 38 patients,there are 19 patients showed solitary type as initial enhancement in MRI,13 grouped types and 6 replaced types.Besides,a total of 25 lesions showed Type ?,2 Type ?,10 Type ?,and 1 Type ?.In this study,different tumor initial enhancements showed no disparity in tumor pathological response grading(Miller-Payne),while Type ? and Type ? have a higher tumor pathological response grading.Type ?(9/10)achieved the most frequently pathological complete response(G=5)rate.There was a low correlation between the size of the tumor evaluated by preoperative ultrasound and postoperative pathology(r=0.201,P=0.226),while a moderate correlation between the size of the tumor evaluated by preoperative MRI and postoperative pathology(r=0.528,P=0.020).Preoperative ultrasound evaluation and postoperative pathology in the patients who initially showed solitary type on US have a low correlation(r=0.348),while there was a moderate correlation between evaluation by preoperative MRI and postoperative pathology(r=0.528,P=0.020).There was almost no correlation between preoperative ultrasound and pathological results in Type ? shrinkage pattern breast cancer patients(r=-0.144).while there was a moderate correlation between evaluation by preoperative MRI and postoperative pathology(r=0.595)ConclusionsOur study showed the tumor shrinkage pattern on MRI after NAC could be used as a predictor of therapeutic efficacy of NAC.Type ? and Type ? shrinkage pattern achieved the most frequently CR rate on the tumor pathological response grading.For patients who showed the grouped type of tumor initial enhancement and type ?shrinkage pattern,using MRI may increase the accuracy of preoperative evaluation in patients...