最小表观扩散系数值评价成人颅内室管膜瘤Ki-67增殖指数的价值

The value of minimum apparent diffusion coefficient value in evaluating Ki-67 proliferation index of adult intracranial ependymoma

目的探讨最小表观扩散系数(minimum ADC,ADCmin)值评价成人颅内室管膜瘤Ki-67增殖指数表达水平的价值。材料与方法回顾性分析2015年5月至2020年3月我院经手术病理证实并进行Ki-67增殖指数测定的29例成人颅内室管膜瘤患者的术前常规MR及扩散加权成像资料,在ADC图上测量肿瘤实质成分ADCmin值,计算ADCmin值与Ki-67增殖指数表达的相关性,按Ki-67增殖指数数值将其分为高表达组(Ki-67≥10%)与低表达组(Ki-67<10%),并进行两组间ADCmin值的比较,绘制受试者操作特征(receiver operating characteristic,ROC)曲线评价ADCmin值判断Ki-67增殖指数表达水平的性能。结果成人颅内室管膜瘤ADCmin值与Ki-67增殖指数间呈负相关(r=-0.596,P<0.01)。Ki-67增殖指数高表达组的ADCmin值明显小于低表达组,应用ADCmin值鉴别Ki-67增殖指数高、低表达组的AUC值为0.897,以0.871×10^-3 mm^2/s作为最佳区分阈值时,其区分Ki-67增殖指数高低水平表达组的敏感度与特异度分别为81.3%、92.3%。结论ADCmin对术前无创预测成人颅内室管膜瘤Ki-67增殖指数表达水平、评估其恶性程度具有潜在价值。

Objective:To explore the value of minimum apparent diffusion coefficient(ADCmin)value in evaluating Ki-67 proliferation index expression in adult intracranial ependymal tumors.Materials and Methods:A retrospective analysis of the preoperative routine MR and DWI data of 29 adult patients with intracranial ependymoma confirmed by surgical pathology and Ki-67 proliferation index in our hospital from May 2015 to March 2020.The ADCmin value of tumor parenchymal components was measured on the ADC maps,and the correlation between ADCmin value and Ki-67 proliferation index expression was calculated.According to Ki-67 proliferation index value,it was divided into high expression group(Ki-67≥10%)and low expression group(Ki-67<10%),and compare the ADCmin value between the two groups,using receiver operating characteristics(ROC)curve to evaluate the ADCmin value to judge the performance of Ki-67 proliferation index expression level.Results:There was a negative correlation between ADCmin value of adult intracranial ependymal tumor and Ki-67 proliferation index(r=-0.596,P<0.01).The ADCmin value of the Ki-67 proliferation index high expression group was significantly smaller than that of the low expression group.When uses the ADCmin value to identify the high and low expression groups of the Ki-67 proliferation index,the AUC value was 0.897,with 0.871×10^-3 mm^2/s is used as the best discrimination threshold,the sensitivity and specificity of the high and low-level Ki-67 proliferation index are 81.3%and 92.3%,respectively.Conclusions:ADCmin has potential value for non-invasively predicting Ki-67 proliferation index expression level and evaluating its malignancy in adult intracranial ependymal tumors.