MRI And Ki67 Predicting The Response Of Neoadjuvant Chemotherapy In Breast Cancer Patients

Objective:This study aims to evaluate the role of MRI and Ki67predicting pathological complete response in patients with breast cancer treated with neoadjuvant chemotherapy.Methods:A total of 112 patients diagnosed with breast invasive carcinoma confirmed by core needle biopsy from January 2016 to December2017 in the Breast Center of Hebei Medical University Fourth Hospital were included for neoadjuvant chemotherapy.The breast DCE-MRI and DWI examination were performed 7 days before chemotherapy as baseline,then for three weeks percycle,before 3and 5 cycles of neoadjuvant chemotherapy and before surgery breast DCE-MRI and DWI examination were performed.For one week percycle,before 7 cycles and surgery.When DWI examination performed,collecting the corresponding apparent diffusion coefficient?ADC?value of the tumor.The ADC value before neoadjuvant chemotherapy was recorded as preADC.The ADC value of the first MRI assessment was recorded as postADC.Then calculate?ADC=postADC-preADC.The method of tumor regression shrinkage patterns were also recorded.After all neoadjuvant chemotherapy was completed,standard surgical treatment or breast-conserving surgery were performed.The the specimens were sent for pathological examination and analyzed according to the Miller and Payne grading system?MPgrade?^[1].This study was based on MRI monitoring the chemotherapy response in breast tumors.Chemotherapy response was divided into two groups based on MP grade,tumor tissue PCR?MP5 grade?and tumor tissue non-PCR?MP1-4 grade?.This study defind MP5 grade is disappearance of invasive cancer cells in breast but but the in situ cancer cells could be combined.Axillary lymph node status was not considered in this study.Chi-square test of the clinicopathological features of patients was used between the PCR group and non-PCR group.PreADC,postADC and?ADC values were compared between PCR and non-PCR using t test.The ROC curve of?ADC and Ki67predicting PCR before chemotherapy was used to find out a cutoff value.Results:1.Analysis of the clinical biological characteristics of the enrolled patients112 patients were enrolled.After neoadjuvant chemotherapy,16 cases obtained tumor tissue PCR were obtained,and 96 cases non-PCR.After statistical analysis,the age,menstrual status,tumor T staging,chemotherapy regime,HER2 status,and Ki67 expression status were not statistically different in tumor tissue PCR group and non-PCR group.Compared with ER-positive and PR-positive tumors,ER-negative,PR-negative tumors were more likely to achieve PCR.In molecular subtype,HER2 positive and triple-negative breast cancers were more likely to reach PCR,followed by Luminal B.Despite the same chemotherapy regimen,none of the Luminal A tumors reached PCR.2.Relationship between Changes of ADC values and PCRThe ADC value before neoadjuvant chemotherapy showed no difference between the PCR and non-PCR group?0.999vs1.005×10-3mm2/s,P=0.902?.After chemotherapy,there was a statistically significant difference in ADC values?1.408vs 1.170×10-3mm2/s,P=0.004?.It showed that after neoadjuvant chemotherapy,the ADC values increased in the two groups,and the ADC value of the PCR group increased more.The tumor tissue PCR was evaluated by?ADC,and the area under the ROC curve was AUC=0.789?95%CI:0.674-0.903?.The?ADC can be considered to be used to evaluate tumor tissue PCR.?ADC cutoff value was>0.245×10-3mm2/s,the sensitivity was83.3%,and the specificity was 68.4%.ADC changes before and after neoadjuvant chemotherapy can predict tumor tissue PCR.3.Relationship between breast cancer molecular subtype and ADC valuePreADC in the four subtypes of Luminal A,Luminal B,HER2?+?and triple negative were 1.018,0.995,1.028,1.028×10-3mm2/s,respectively?P=0.879?.PostADC were 1.320,1.168,1.346,and 1.261×10-3 mm2/s,respectively?p=0.246?.?ADC were 0.188,0.174,0.270,and 0.276×10-3mm2/s,respectively?p=0.560?,and the differences were not statistically significant.There was no correlation between ADC value and molecular subtypes.4.Relationship between MRI tumor shrinkage patterns and PCRTumor shrinkage patterns after neoadjuvant chemotherapy for breast cancer can be divided into centripetal shrinkage and fragmentary shrinkage.There was no correlation between tumor shrinkage patterns and molecular subtypes.5.The relationship between Ki67 and PCRThe ROC curve of Ki67 predicting PCR was evaluated.The area under the curve was AUC=0.691?95%CI:0.561-0.820?.Ki67 before chemotherapy can be considered to be used for evaluation.Ki67 cutoff value was>45%.Sensitivity was 62.5%and specificity was 66.7%.Ki67 expression has a certain value in the prediction of tumor tissue PCR.Conclusions:1.Among clinical and pathological features,ER-negative or PR-negative tumors were more likely to reach tumor tissue PCR.HER2-positive and triple-negative breast cancers were more likely to reach tumor tissue PCR,followed by Luminal B,and the last was Luminal A.2.Changes in ADC values after neoadjuvant chemotherapy can predict tumor tissue PCR.3.Changes in tumor ADC after neoadjuvant chemotherapy have nothing to do with molecular subtype.4.Tumor shrinkage patterns can not predict tumor PCR.5.Ki67 predicting tumor tissue PCR ROC curve shows that before chemotherapy Ki67 can predict tumor PCR.