Clinical Value Of High Frequeney Ultrasound Combined With Shear Wave Elastography In The Evaluation Of Chest Wall Radiation Dermatitis In Breast Cancer Patients Undergoing Radiotherapy

Objectives:To explore the effect of high frequency ultrasound(HUFS)and shear wave elastography(SWE)on skin thickness and hardness in different stages of postoperative radiotherapy in patients with breast cancer,and to assist radiation therapy oncology group(RTOG)grading in the diagnosis of radiation skin damage.Methods:There were 54 female breast cancer patients who were treated with radiotherapy in our hospital and 44 healthy adult women.The skin thickness ratio(STRA)and elasticity ratio(SERA)of bilateral anterior chest wall were measured by SWE combined with HFUS.Breast cancer patients were measured with the same method 4 times before radiotherapy(Baseline),at the end of the 1、3、5 week of radiotherapy.Before each examination,the radiologist used RTOG acute radiation injury classification standard to evaluate the chest wall skin of breast cancer patients treated with radiotherapy,and compared the thickness and hardness of chest wall skin between breast cancer patients(Baseline)and normal group.The changing trend of skin thickness and elasticity with time under different segmentation doses was analyzed.The real clinical data and anthropometric parameters of simulated CT breast were collected,and the correlation with skin thickness and elasticity was analyzed.Results:①The STRA and SERA of breast cancer patients with different surgical methods were different from those of the normal group(P<0.05).②Both the times of radiotherapy and the mode of operation could significantly affect the changes of STRA and SERA in patients with breast cancer.STRA will increase with the increase of radiotherapy times,and the change trend of different surgical methods was the same(F=0.808,P=0.495).The changing trend of SERA with the times of radiotherapy was significantly different with the mode of operation.The interaction between the times of radiotherapy and the mode of operation was significant(F=3.858,P=0.015).There was no significant change in SERA in patients undergoing breast conserving surgery,but SERA in patients undergoing radical mastectomy increased significantly with the increase of radiotherapy times.③The changes of STRA and SERA in patients with breast cancer were correlated with the increased risk of RTOG grade,STRAx10(OR=1.57,95%CI 1.24-1.99)and SERA(OR=1.65,95%CI 1.28-2.14).④The increase of RTOG grade at the end of radiotherapy was correlated with the mode of axillary operation(OR=3.8,95%CI 1.03-13.96,P<0.05).Conclusion:With the increase of the times of radiotherapy,different surgical methods had different effects on the thickness and elasticity of chest wall skin in patients with breast cancer.STRA、SERA and axillary lymph node surgery are closely related to the increased risk of skin toxicity.HFUS combined with SWE evaluation can assist in quantitative monitoring of skin toxicity in breast cancer patients receiving radiotherapy,provide objective imaging basis for clinical decision-making.