DWI在早期评估骨肉瘤新辅助化疗疗效中的应用价值

Application value of diffusion weighted imaging in early evaluation of neoadjuvant chemotherapy for Osteosarcoma

目的:探讨磁共振扩散加权成像(DWI)在早期评估骨肉瘤化疗疗效中的应用价值。方法:搜集行新辅助化疗的骨肉瘤患者11例,患者分别于新辅助化疗开始前、第1个化疗周期结束后、所有4个化疗周期结束后行常规MRI及DWI检查,检测骨肉瘤内水分子扩散及血液灌注变化情况,观察新辅助化疗过程中骨肉瘤形态、大小结构等方面的变化情况。结果:9例患者化疗后肿瘤体积增大,2例患者化疗后肿瘤体积变小或不变,化疗前与化疗早期的ADC值差异有统计学意义(P<0.05)。将化疗前、化疗第1周期结束后的ADC值及两次ADC变化量与肿瘤坏死率进行相关性分析,其中ADC值变化量与肿瘤坏死率存在相关性(r=0.397,P=0.020)。结论:化疗第1周期结束时ADC值变化量可以反映肿瘤坏死率情况,为预测新辅助化疗效果、评估治疗方案提供新的影像学思路。

Objective:The purpose of this study was to evaluate the value of diffusion weighted imaging(DWI)in predicting the efficacy of neoadjuvant chemotherapy for osteosarcoma at early stage.Methods:Eleven patients with osteosarcoma treated with neoadjuvant chemotherapy in the First Affiliated Hospital of Guangxi Medical University from 2017 to 2019 were collected.MRI scan(conventional and DWI)was performed before neoadjuvant chemotherapy,after the end of the first stage,after all four stages of chemotherapy.The diffusion of water molecules and the changes of blood perfusion in osteosarcoma were detected,and the morphology,size and structure of osteosarcoma were observed during neoadjuvant chemotherapy.Results:The tumor volume increased in 9 patients and decreased or remained unchanged in 2 patients after chemotherapy.The difference between the ADC values before and after the first stage of chemotherapy were statistically significant(P<0.05).Correlation analysis was made between the ADC value before chemotherapy,after the first stage of chemotherapy and the change of ADC value with tumor necrosis rate.There was a correlation between the change of ADC value and tumor necrosis rate(r=0.397,P=0.020<0.05).Conclusion:The changes of ADC value at the end of the first stage of neoadjuvant chemotherapy for osteosarcoma can reflect the situation of tumor necrosis rate,which can be used as a new approach to predict the efficacy of neoadjuvant chemotherapy.