表观扩散系数在胰腺癌放疗疗效定量评价中的应用

目的探讨MRI检查中表观扩散系数(ADC)在胰腺癌放疗后疗效评价中的作用。方法26例接受放射治疗的胰腺癌患者,分别于放射治疗前、放疗后1、3和6个月行磁共振成像(MRI)检查,对弥散加权成像(DWI)序列的ADC值进行测量。同时测量肿瘤最大径,根据肿瘤最大径放疗前后的变化率将病例分为缓解组和未缓解组,运用SPSS17.0软件统计分析表观扩散系数在放疗前后的变化及其与肿瘤最大径变化率之间的关系。结果全部26例胰腺癌患者的放疗后ADC值均明显升高(P<0.001);缓解组放疗前ADC值明显低于未缓解组(P<0.05);26例患者的放疗前ADC值与肿瘤最大径缩小率呈负相关(P<0.01)。结论胰腺癌放疗前后ADC值的变化对胰腺癌放疗后(特别是病灶体积未发生明显变化时)的疗效评价有重要价值,对预测肿瘤放疗后体积缩小的程度、判断肿瘤放疗治疗的效果也有一定价值。

Apparent diffusion coefficient in the evaluation of the therapeutic effect of radiotherapy for pancreatic cancer

Objective To investigate the role of apparent diffusion coefficient(ADC)value in the evaluation of therapeutic effect of radiotherapy for pancreatic cancer.Methods Twenty six patients with pancreatic cancer received radiotherapy were examined with magnetic resonance imaging(MRI)before radiotherapy,one month after radiotherapy,three months after radiotherapy,and six months after radiotherapy,and ADC value of diffusion weighted imaging(DWI)was measured.The patients were divided into remission group and non-remission group according to the change rate before and after radiotherapy,SPSS17.0 software was used to analyze the change of apparent diffusion coefficient before and after radiotherapy and the relationship between the change rates of tumor maximum diameter.Results The ADC value of 26 patients with pancreatic cancer increased significantly after radiotherapy(P<0.001);the ADC value of the remission group was significantly lower than that of the non-remission group before radiotherapy(P<0.05);the ADC value of 26 patients before radiotherapy was negatively correlated with the tumor maximum diameter reduction rate(P<0.01).ConclusionsThe change of ADC value before and after radiotherapy is of great value to the radiotherapy for pancreatic cancer,especially to the evaluation of the curative effect when the volume of the focus has not changed significantly.It is also of certain value to predict the degree of volume reduction after radiotherapy and to judge the effect of radiotherapy for pancreatic cancer.