表观弥散系数值与Ki-67在胶质瘤诊断中的相关性

Correlation of Apparent Diffusion Coeffcient with Ki-67 in the Diagnosis of Gliomas

目的探讨表观弥散系数(ADC)值与Ki-67在胶质瘤诊断中的相关性。方法对76例胶质瘤患者术前进行常规磁共振检查、增强扫描检查及弥散加权成像扫描,测量肿瘤实质部分及相应对侧正常脑白质的ADC值,并计算其相对ADC(rADC)值,分析ADC值及rADC值与胶质瘤病理分级的关系。采用免疫组织化学染色方法对76例胶质瘤的Ki-67表达进行观察,测定Ki-67标记指数,分析ADC值与Ki-67表达程度诊断胶质瘤的相关性。结果高级别胶质瘤肿瘤实质部分ADC值和rADC值明显低于低级别胶质瘤,即胶质瘤肿瘤实质部分ADC值及rADC值与肿瘤的恶性度呈负相关(r=-0.898,r=-0.868;P均<0.01);高级别胶质瘤中Ki-67的表达程度高于低级别胶质瘤,Ⅲ、Ⅳ级胶质瘤Ki-67标记指数分别为(29.48±19.78)%和(31.21±17.50)%,均高于低级别(Ⅰ、Ⅱ级)胶质瘤(2.33±2.20)%,差异均有统计学意义(P<0.01),但Ⅲ、Ⅳ级胶质瘤间Ki-67标记指数差异无统计学意义(P>0.05);Ki-67表达程度与肿瘤实质部分ADC值及rADC值呈负相关(r=-0.627,r=-0.607;P<0.01)。结论胶质瘤瘤体实质区ADC值和rADC值对胶质瘤病理分级诊断具有重要意义,根据胶质瘤实质部分ADC值及rADC值的测量,可间接评估肿瘤的增殖程度及恶性程度。

Objective To study the correlation between apparent diffusion coefficient （ADC） and Ki-67, a marker of tumor activity, in the diagnosis of gliomas. Methods Conventional magnetic resonance imaging （MRI）, enhanced scanning, and diffusion-weighted imaging were performed in 76 patients with patho- logically confirmed gliomas. The ADC values were measured at tumor parenchyma and the corresponding contra- lateral normal brain. The relatively ADC （rADC） values of the tumor parenchyma were calculated. The corre- lation of the ADC values with tumor grades was analyzed. The expression of Ki-67 was detected by immunohis- tochemical staining. The correlation between ADC value and Ki-67 in the diagnosis of gliomas was analyzed. Results The ADC values and rADC values of high-grade gliomas were significantly lower than those of low- grade gliomas. The ADC values of tumor parenchyma were inversely associated with the degree of malignancy of the gliomas （r = - 0. 898, r = - 0. 868; P 〈 0. 01）. The high-grade gliomas than that in low-grade gliomas. The Ki-67 expression of Ki-67 was signifi labeling index in grade I!1 and cantly higher in IV gliomas were （29.48± 19.78 ）% and （31.21 ± 17.50 ） %, respectively. Both of them were significantly higher than Ki- 67 labeling index in low-grade （ grade I and II ） gliomas [ （2.33 ± 2.20） % ] （ P 〈 0.01 ）. Nevertheless, the Ki-67 labeling index showed no significant difference between grade III and IV gliomas （ P 〉 0.05 ）. The expression of Ki-67 was negatively correlated with the ADC values and rADC values in tumor parenchyma （ r = - 0. 627, r = - 0. 607 ; P 〈 0. 01 ）. Conclusion The ADC and rADC values of tumor parenchyma can in- directly reflect the proliferation and malignancy of gliomas and therefore can be useful for the grading of glioma.