Application Value Of Elastic Parameters Of Peritumoral Tissue In Diagnosis Of Breast Cancer

Objective:To observe the correlation between the parameters of Sound Touch Elastography(STE)and the expression of biomarkers in breast cancer and 2mm tissue around the tumor,to explore the value of STE in the clinical diagnosis of breast cancer,and to provide theoretical basis for clinical application.Methods:252 breast lesions from 252 patients who received ultrasound examination in the breast department of our hospital from July,2018 to June,2020 were included in the study.Inclusion criteria :(1)breast mass diameter less than 3cm;(2)Elastic ultrasound images must adequately include glandular tissue of at least 2mm around the mass;(3)The patient did not undergo any invasive examination or interventional treatment before ultrasound examination;(4)Breast masses assessed by ultrasound as Category 3,4 and 5 BI-RADS;(5)All patients received tissue biopsy or surgical treatment and obtained pathological diagnosis results;(6)The patient knows and signs the informed consent.All lesions were examined by conventional ultrasound and STE imaging before operation,and their indexes were observed and recorded.The young’s modulus(Kpa)of the tumor(E: Emax,Emean,Emin,Esd)and the surrounding 2mm glandular tissues(S: Smax,Smean,Smin,Ssd)were collected with STE elastic quantitative parameters.Using histopathological results as the gold standard,ROC curve was used to evaluate the diagnostic value of various elastic quantitative parameters in breast tumor and peritumor tissues.The optimal critical value of peritumoral Smax and the intratumoral Emax truncation value were used to perform the four-grid Mc Nemar test to compare whether there was statistical significance between the peritumoral and intratumoral diagnostic models.In this study,the molecular biological indicators of breast cancer patients were divided into high expression group and low expression group according to the expression of ER,PR,HER-2 and Ki-67,and the difference of peritumoral STE parameters between high and low expression groups was compared.Results:1.Compared with benign tumors,Emax,Emean,Esd,Smax,Smean and Ssd were significantly increased in breast cancer(P < 0.001).There were no significant differences in Emin and Smin between benign and malignant tumors(P > 0.05).The results showed that the hardness of breast cancer tissue was significantly increased both inside and around the tumor.2.Compared with intratumoral elastic parameters,the area under curve(AUC)of elastic parameters Smax,Smean and Ssd in periatumoral tissues was larger than that of the corresponding intratumoral elastic parameters Emax,Emean and Esd.The AUC of Smax was the highest,and the difference between Smax and Emax was statistically significant(P< 0.05).This indicates that the diagnostic efficiency of peritumoral elastic parameter is higher than that of intratumoral elastic parameter,and the peritumoral elastic parameter Smax has the highest diagnostic efficiency.3.The comparison of the optimal threshold values of peritumoral Smax 90.37 Kpa,intratumoral Emax 72.12 Kpa and 60 Kpa for the diagnosis of breast cancer showed that the Mc Nemar test showed a statistically significant difference between the two threshold values of peritumoral Smax and intratumoral Emax(P < 0.05).The difference in diagnostic value between peritumoral Smax and intratumoral Emax was statistically significant.The Yuden index of peritumoral Smax was higher than that of intratumoral Emax(0.518 vs.0.426 vs.0.335),indicating that the diagnostic effect of peritumoral Smax was better than that of intratumoral Emax.ROC curve analysis showed that the AUC of peritumoral Smax was significantly higher than that of intratumoral Emax(0.759 vs.0.714 vs.0668),indicating that the diagnostic ability of peritumoral Smax was higher than that of intratumoral Emax.4.Correlation analysis between the expression level of commonly used molecular biomarkers of breast cancer and peritumoral STE parameters :(1)compared with the lowexpression group of ki-67,young’s modulus values of Smax,Smean and Ssd in the highexpression group of ki-67 were significantly increased(P < 0.05).The results indicated that the hardness of peritumoral tissue in the group with high expression of KI-67 was significantly higher than that in the group with low expression of Ki-67.(2)Young’s modulus values of peritumoral Smax,Smean and Ssd in ER,PR positive group and HER-2 positive group were lower than those in ER,PR positive group and HER-2 negative group,but the difference was not statistically significant(P > 0.05).The results showed that there was no significant difference in the hardness of peritumoral tissues between ER,PR and HER-2 groups.(3)Peritumoral Smax and Smean elastic parameters in each molecular subtype of breast cancer,the modulus values from large to small are: There was no significant difference in her-2 overexpression type > Basal-like type > Luminal B type >Luminal A type(P > 0.05),indicating that there was no significant difference in hardness of peritumoral tissues among different molecular subtypes of breast cancer.Conclusion:1.Elastic quantitative parameters of peritumoral and intratumoral tissues of breast masses are helpful for differentiating benign and malignant tumors,among which Smax of peritumoral tissues has the greatest diagnostic value and can be used as a beneficial supplement for BI-RADS evaluation.2.Elastic parameters of peritumoral tissues can be used as a predictor of the expression level of molecular biological factor Ki-67 in breast cancer,providing an important reference for preoperative and prognostic evaluation of breast cancer.