Role of Magnetic Resonance Imaging in Estimating the Response

Role of Magnetic Resonance Imaging in Estimating the Response of Breast Cancer to Neoadjuvant Chemotherapy & Role of the ADC Value in Estimating and Predicting the Response of Breast Cancer to Neoadjuvant Chemotherapy: A Pilot Study with Diffusion-Weighte
　　Part One:Role of Magnetic Resonance Imaging in Estimating the Response of Breast Cancer to Neoadjuvant ChemotherapyBackground:Neoadjuvant chemotherapy has become one of the most important parts of treatment in breast cancer.But to date,there is still short of a method which can accurately and efficiently assess the response to neoadjuvant magnet lifter chemotherapy.Recently, a series of studies conducted in the western countries documented that magnetic resonance imaging(MRI) can accurately evaluate chemotherapeutic response,while there were still few studies conducted in our country.However,many studies indicated that MRI may overestimate or underestimate the residual disease in patients receiving neoadjuvant chemotherapy.The role of MRI in assessing the response of breast cancer to neoadjuvant chemotherapy needs further study.Objective:①To approach the value of MRI in estimating the morphology of the tumor in breast cancer patients receiving magnet lifter neoadjuvant chemotherapy.②To compare the accuracy of MRI with sonography and clinical assessment in assessing the residual disease,and to compare the accuracy of MRI with sonography in assessing the response of breast cancer to neoadjuvant chemotherapy.Methods:A total of 22 breast cancer patients participated in this prospective study on neoadjuvant chemotherapy.They were examined by MRI and sonography before chemotherapy,after the second cycle and after the fourth cycle of chemotherapy.
　　The shrinkage patterns of the tumor appeared on MRI and their relationship with histological type,ER/PR expression with IHC,Her2 status with IHC,treatment regimen was examined.We also investigated the relative value of MRI,sonography and clinical assessment in assessing the residual disease and the relative value of MRI and sonography in assessing the response compared with pathological examination, and the relationship between the treatment regimen and the accuracy of MRI in estimating the residual disease in patients receiving neoadjuvant magnet lifter chemotherapy.Results:There were two shrinkage patterns.12 of 22 breast cancers(54.5%) showed a concentric shrinkage pattern while 10 cases(45.5%) showed a dendritic shrinkage pattern.ER and PR negative tumors,tumors with Her2 high expression(++～+++), invasive ductal carcinoma and tumors treated with anthracyclines tended to show concentric shrinkage while ER and/or PR positive tumors,tumors with Her2 low expression(-～+),mucinous carcinoma,invasive lobular carcinoma and tumors treated with taxanes or vinorelbine tended to show dendritic shrinkage.
　　A strong correlation(r=0.781,P<0.001) was observed between the longest diameter of residual disease measured on MRI and pathology while the longest diameter measured on sonography(r=0.574,P=0.005) and clinical assessment(r=0.450,P=0.036) only showed moderate correlation with pathologic results.The error of the longest diameter measured on MRI compared with pathologic results(0.51±0.55cm) was also less than that measured on sonography(0.73±0.78cm) and clinical assessment (1.27±0.93cm) compared with pathologic results.There was no significant difference between sonography and MRI in assessing the response(CR,PR,SD,PD) to neoadjuvant chemotherapy(P=0.754).The sensitivity,specificity,positive predictive value and negative predictive value of MRI in magnet lifter diagnosis of pathologic complete response(pCR) were higher than those of sonography(83.3%,100.0%, 100.0%,94.1%vs.66.7%,93.8%,80.0%,88.2%),and the false positive rate and false negative rate of MRI in diagnosis of pCR were lower than those of sonography(0.0%,16.7%vs.6.2%,33.3%).The overall agreement of response as measured on MRI and sonography compared with pathology was 95.5%and 86.4%, respectively.MRI underestimated the residual disease in 2 cases and overestimated the residual disease in 4 cases.
　　The correlation between MRI after chemotherapy and histology was 0.868(P=0.005) in anthracyclines treated group,which was higher than that in taxanes(r=0.777,P=0.008) or vinorelbine(r=0.594,P=0.406) treated group.Conclusions:MRI is a useful modality for evaluating the morphology of the tumor in breast cancer patients receiving neoadjuvant chemotherapy.MRI can estimate the residual tumor extent after neoadjuvant chemotherapy more accurately than sonography and clinical assessment,and MRI also can estimate the response to neoadjuvant chemotherapy more accurately than sonography. Part Two.Role of the ADC Value in Estimating and Predicting the Response of Breast Cancer to Neoadjuvant Chemotherapy:a Pilot Study with Diffusion-Weighted MRIBackground:Neoadjuvant chemotherapy has been accepted as the standard treatment of locally advanced breast cancer.But to date,there is still short of a method which can accurately assess and early predict response to neoadjuvant chemotherapy.A number of recent preclinical animal studies and cell models have indicated the potential magnet lifter usefulness of diffusion-weighted imaging(DWI) in predicting response to the treatment of cancers.Till now,few papers demonstrating the similar results in human studies have been published.However,DWI has been utilized to assess response to treatment in brain tumors,metastatic liver lesions and rectal carcinomas. The role of diffusion-weighted magnetic resonance imaging in assessing the response of breast cancer to neoadjuvant chemotherapy needs further study.Objective:To approach the ADC value obtained on DWI in estimating and predicting the response of breast cancer to neoadjuvant chemotherapy. Methods:A total of 35 breast cancer cases participated in this prospective study on neoadjuvant chemotherapy.12 cases of them who have finished neoadjuvant chemotherapy underwent surgery,and were examined by DWI before chemotherapy, after the second cycle of chemotherapy and before surgery(1 case of them was excluded because there was no residual disease showed on MRI before surgery).23 cases who have not finished neoadjuvant chemotherapy were examined by DWI before chemotherapy and after the first cycle of chemotherapy.We assessed the appearances of tumor on DWI.Of the 11 patients,we assessed the relationship between the degree of the changes in ADC value and the degree of the changes in the longest diameter of tumor measured on MRI and the relationship between the changes in ADC values and age,ER/PR expression with IHC,Her2 status with IHC and the response to neoadjuvant chemotherapy.We also assessed whether the ADC value before neoadjuvant chemotherapy could predict the response of breast cancer and the degree of the changes in the longest diameter of tumor.We estimated the relationship between the size reduction in neoadjuvant treatment of breast cancer and the changes in ADC value after the magnet lifter  first cycle or the second cycle of chemotherapy.
　　Results:Of the 11 cases,a strong negative correlation was observed between the degree of the changes in ADC value and the degree of the changes in the longest diameter of tumor measured on MRI(r=-0.729,P=0.011).Age and Her2 status were not significantly associated with the changes in ADC value,but both ER and PR negative patients were likely to have greater changes in ADC value than ER and/or PR positive patients(-0.14±0.13 vs.-0.50±0.28,P=0.027).This phenomenon was also seen in the changes in the longest diameter(P=0.011).9 of 11 cases were diagnosed partial disease(PR) by MRI and 2 of 11 cases were diagnosed stable disease(SD) by MRI after chemotherapy.The mean ADC value of the posttreatment was increased more significantly in the PR group(0.41±0.26,P=0.002) than in the SD group(0.02±0.01,P=0.205).A strong negative correlation was also observed between the ADC values,measured prior to treatment,and the degree of the changes in the longest diameter after therapy(r=-0.793,P=0.004).A significant difference between the mean ADC value of PR group and SD group was shown before chemotherapy(1.00±0.10 vs.1.27±0.10,P=0.006).Of the 11 cases,both the increase in the ADC value(P=0.002,P=0.002) and the decrease in the longest magnet lifter diameter(P=0.001,P<0.001) were significant after the second cycle of neoadjuvant chemotherapy and before surgery.It was noted that of the 23 cases,there was a significant increase in the ADC value at the first cycle time point(P<0.001),while the decrease in the longest diameter was not significant(P=0.103).Conclusions:The ADC value obtained on Diffusion-weighted MR imaging is potentially useful in detecting the response of breast cancer to neoadjuvant chemotherapy,and the ADC value before chemotherapy can predict the response of breast cancer and the degree of the changes in the longest diameter http://www.999magnet.com/ of tumor.The increase in the ADC value at the first cycle time point may predict the early response of breast cancer to neoadjuvant chemotherapy.