Analysis Of Changes In Triple-negative Breast Cancer Before And After Neoadjuvant Chemotherapy Based On Raman Spectroscopy

ObjectiveRaman spectroscopy is a technique for studying vibrating chemical particles.By analyzing the information of chemical particles,qualitative and quantitative analyses of the chemical substances in the sample are carried out.The purpose of this study is to analyze the changes in tissues composition of triple-negative breast cancer before and after neoadjuvant chemotherapy by referring to normal breast tissues and applying Raman spectroscopy.MethodsFrom July 2015 to July 2019,we screened out qualified patients among the breast cancer patients who had been treated in breast surgery of our hospital.The pathological results of these TNBC patients were all non-specific invasive ductal carcinoma of the breast,and their immunohistochemical markers were all negative for ER,PR and Her-2.The relevant data of the patients were collected.According to the National Comprehensive Cancer Network（NCCN）guidelines and in combination with the patient’s basic situation,all patients received TEC chemotherapy regimen（T:docetaxel,E:epirubicin,C:cyclophosphamide,with corresponding dose according to the patient’s body surface area）,and the preoperative neoadjuvant chemotherapy was administered for 6 cycles.Clinically,according to the RECIST guidelines,the maximum two diameters of tumors before and after neoadjuvant chemotherapy were investigated by ultrasound meridian measurement to evaluate the effect of neoadjuvant chemotherapy for breast cancer,and pathologically Miller-Payne（MP）grading system was used to evaluate the effect of neoadjuvant chemotherapy for breast cancer.All sample tissues in this study used formalin fixation and paraffin embedding（FFPE）.These tissues were obtained from biopsy before neoadjuvant chemotherapy and tissue samples surgically removed after neoadjuvant chemotherapy.All tissue samples were obtained from the clinical pathology department,and two consecutive 2 micron thick sections were collected from each sample（one used for histological examination,another used for Raman spectroscopy detection）.After dewaxing and standardized procedures,one section was stained with hematoxylin-eosin（HE）.Routine histopathological analysis was performed by two clinical pathologists to identify the most prominent area of the lesion.The same location was marked in another unstained section.After ultrasound meridian evaluation and pathological evaluation（MP grading system）,the patients were divided into partial remission group and stable group.All tissue samples were divided into six groups,including data before neoadjuvant chemotherapy for triple-negative breast cancer,data after neoadjuvant chemotherapy for triple-negative breast cancer and data of normal breast tissue.Raman spectroscopy detection was carried out in turn in groups,and the received Raman data was imported into the Origin8.5 software for drawing.All the Raman spectroscopy images were normalized and smoothed by classification and then compared and analyzed.ResultFrom the obtained Raman spectroscopy,the patients in the partial remission group showed obvious peaks of carotenoids(1158cm^-1,1518cm^-1)in the Raman spectroscopy of triple-negative breast cancer tissues after neoadjuvant chemotherapy;After neoadjuvant chemotherapy,the Raman spectroscopy of triple-negative cancer tissues were similar to that of normal breast tissues.After neoadjuvant chemotherapy,the concentration of saturated fatty acids(2888cm^-1,2926cm^-1)and phospholipids(1264cm^-1)in triple-negative breast cancer tissues decreased.Patients in the stable group:There was no significant change in the Raman spectroscopy of triple-negative breast cancer tissues before and after neoadjuvant chemotherapy,the intensity of the saturated fatty acid peak was reduced,and there was no obvious carotenoid peak.For the triple-negative breast cancer tissues before neoadjuvant chemotherapy,patients with stable chemotherapy response compared with patients with partial remission,the main difference is the higher concentration of phospholipid peak and saturated fatty acid.Conclusion1.There is a change in the Raman spectroscopy of patients with partial remission of neoadjuvant chemotherapy for triple-negative breast cancer;2.Patients with stable neoadjuvant chemotherapy have no significant change in Raman spectroscopy,and Raman spectroscopy can be used as a method to evaluate the effect of neoadjuvant chemotherapy for triple-negative breast cancer;3.Through the detection of triple-negative breast cancer tissues before neoadjuvant chemotherapy,Raman spectroscopy can predict that triple-negative breast cancer patients will need further study later;4.Raman spectroscopy can guide triple-negative breast cancer patient’s neoadjuvant chemotherapy regimen needs further observation.