MRI Assessment Of Neoadjuvant Chemotherapy Efficacy In Breast Cancer With Non-concentric Shrinkage Mode

Objective of the study:Breast tumors can show Different shrinkage modes after neoadjuvant chemotherapy,and the different Different shrinkage modes are important factors affecting the surgical approach and extent of resection after neoadjuvant chemotherapy.When the tumor shows non-centric shrinkage(NCS),its imaging assessment is difficult.In this paper,we intend to investigate the accuracy of MRI assessment of neoadjuvant chemotherapy(NAC)efficacy in non-centric shrinkage(NCS)modes breast cancer and its influencing factors.Methods:In this study,680 breast cancer patients undergoing neoadjuvant chemotherapy from January 2019 to October 2022 were retrospectively analyzed,and a total of 66 study subjects meeting the criteria were enrolled according to the inclusion and exclusion criteria.Firstly,MRI images of each series before and after chemotherapy were acquired from each patient and transferred to 3D-slice workstation for processing to obtain the 3D volume of the lesion.The early intensification rate,ADC value,tumor intensification volume and other index parameters as well as general clinical features,pathological types,molecular typing and other information parameters were recorded before and after chemotherapy in each group.The patients were divided into significant remission group and non-significant remission group according to the RCB pathological assessment criteria,and the differences in parameters between these two groups were analyzed univariately using independent sample t-test,rank sum test,and chi-square test,respectively,and then the parameters with statistically significant differences in the univariate factors were subjected to binary logistic regression analysis to screen out the relevant influencing factors of NAC efficacy.Kendall correlation analysis was applied to analyze the strength of the correlation between NAC efficacy and each parameter.In addition,the sensitivity and specificity of DCE-MRI alone and DCE-MRI combined with DWI were compared and analyzed,and the difference in consistency with the results of pathological assessment was analyzed.Finally,ROC curves were plotted based on MRI-related parameters such as tumor enhancement volume change rate(Δ V%),ADC value change rate(Δ ADC%),and early enhancement change rate(Δ E%),and the diagnostic efficacy of each parameter on the efficacy of NAC and pathological complete remission(pCR)was evaluated according to the area under the curve AUC.Results:(1)The pattern of non-central shrinkage of breast cancer may be closely related to the mode of non-mass enhancement before chemotherapy,molecular typing,malignant calcification and larger tumors.Non-mass type of enhancement(56.06%)and multifocal type of enhancement(27.27%)were predominant in our study sample;molecular typing was highest in HER-2 overexpression type,and the ki67 high expression group was much higher than the low expression group.The mean tumor volume before chemotherapy was about 79 cm3,and about 83.33% of the cases were accompanied by malignant calcified foci.(2)Univariate analysis affecting the neoadjuvant efficacy of NCS breast cancer showed that molecular typing,(ER,PR,HER-2,Ki67)expression status were important factors influencing the efficacy of NAC in NCS breast cancer,and binary logistic multifactorial regression analysis showed that HER-2 expression status was an independent factor affecting the efficacy of NAC.correlation analysis between the efficacy of NAC and each parameter showed that: There was a significant positive correlation between HER-2 overexpression,HER-2(+),ER(-),PR(-),Ki67 high expression group and NAC efficacy.there was a significant negative correlation between Luminal B1,Luminal A,HER-2(-),ER(+),PR(+),Ki67 low expression status and NAC efficacy.(3)The sensitivity of DCE-MRI evaluation of breast NAC efficacy was 100%,specificity 58.62%,positive predictive value 75.51%,and negative predictive value100%.the Kappa value of agreement between DCE-MRI diagnostic imaging and pathological diagnosis to assess the degree of NAC remission was 0.614,indicating that the agreement between DCE-MRI imaging assessment and pathological assessment was average.the DCE-MRI combined with DWI assessment and DCE-MRI alone to assess NAC efficacy results did not change significantly.(4)DCE-MRI alone evaluated breast pCR with a sensitivity of 52.38%,specificity of100%,positive predictive value of 100%,and negative predictive value of 81.82%.the Kappa value of agreement between DCE-MRI imaging diagnosis and pathology diagnosis assessment of pCR was 0.600,and the agreement between the two diagnoses was moderate.When DCE-MRI combined with DWI evaluated pCR: MRI evaluated breast pCR with 95.24% sensitivity,100% specificity,100% positive predictive value,and 97.82% negative predictive value.pCR consistency Kappa value between DCE-MRI combined with DWI imaging diagnosis and pathology diagnosis evaluation was 0.823,and its agreement with pathology diagnosis was high.This indicates that the sensitivity of DCE-MRI combined with DWI diagnosis is higher than that of DCE-MRI alone in evaluating pCR and the agreement with pathological diagnosis.(5)The results of the diagnostic ROC curves for the efficacy of NAC showed that the AUC values corresponding to ΔV%,ΔADC%,and ΔE% were 0.949,0.878,and 0.772,respectively.pCR predictive efficacy ROC curves for ΔV%,ΔADC%,and ΔE% were0.960,0.817,and 0.768,respectively,indicating that ΔV%,ΔADC%,and Δ E% are of relatively high value for the assessment of NAC efficacy and pCR prediction.(6)The MRI-related parameters of tumor volume V,ADC value,early post-chemotherapy enhancement rate E,and TIC type produced significant changes in the significant remission group and the non-significant remission group after chemotherapy,and the degree of changes were greater in the significant remission group than in the non-significant remission group.Conclusion:1、The pattern of NCS regression in breast cancer may be related to the mode of mass enhancement,molecular typing,and malignant calcification before chemotherapy.2、Molecular typing,(ER,PR,HER-2,Ki67)expression status are all important factors influencing the efficacy of NCS breast cancer NAC,of which HER-2(+)is an independent influence.3、DCE-MRI alone assessed the efficacy of NAC in non-centripetal regression pattern breast cancer with some underestimation of residual lesions,while there was some overestimation of residual lesion assessment in predicting pCR after NAC,and both were in general agreement with RCB pathological assessment.combined DCE-MRI and DWI-MRI assessment of pCR improved the sensitivity of MRI in pCR diagnosis,the accuracy and consistency with RCB pathological assessment,and reduced the overestimation of residual lesions in breast cancer;therefore,the diagnostic value of DCE-MRI combined with DWI assessment for pCR after NAC of breast cancer was higher compared with DCE-MRI assessment alone.4、MRI is an accurate tool to assess the efficacy of NAC in NCS breast cancer,and MRI-related parameters of tumor enhancement volume V,early enhancement rate E,TIC curve type and DWI-related parameter ADC value can be used as important indicators for the assessment of NAC efficacy in NCS breast cancer.