表观扩散系数与Ki-67指数在子宫内膜间质肉瘤病理分级中的相关性研究

Correlation between ADC value and Ki-67 index in the pathological grading of endometrial stromal sarcoma

目的探讨子宫内膜间质肉瘤(ESS)的常规MRI特征,初步分析表观扩散系数(ADC)值与Ki-67指数在ESS病理分级中的相关性。方法回顾性分析26例经手术病理证实的ESS病人的临床及MRI资料,平均年龄(52±13)岁。病理分级为低级别ESS (LGESS,9例)和高级别ESS (HGESS,17例)。分析ESS的MRI形态特征、扩散加权成像(DWI)信号强度,测量肿瘤实性部分ADC值,并进行免疫组化分析,统计Ki-67指数。采用t检验比较高低级别ESS的ADC值和Ki-67指数,采用Pearson相关分析ADC值和Ki-67指数在ESS病理分级中的相关性。结果26例肿瘤T1WI上表现为均匀或不均匀等、低信号,T2WI上表现为不均匀高信号,DWI上肿瘤实性部分呈高信号。HGESS的平均ADC值[(0.74±0.11)×10^-3mm^2/s]低于LGESS的[(1.07±0.24)×10^-3mm^2/s](P<0.05),HGESS的平均Ki-67指数[(45.53±14.23)%]高于LGESS的[(8.33±2.50)%](P<0.05)。ADC值与Ki-67指数呈负相关(r=-0.726,P<0.001)。结论 ESS的MRI表现具有一定的特征,通过测量肿瘤ADC值可以间接评估ESS的病理分级。

Objective To investigate the characteristics of endometrial stromal sarcoma(ESS)on conventional MRI,and to preliminarily analyze the correlation between apparent diffusion coefficient(ADC)value and Ki-67 index.Methods A retrospective analysis was carried out on the clinical and MRI data of 26 patients with ESS confirmed by surgical resection and pathology,with an average age of 52±13 years.The pathological classifications were low-grade ESS(LGESS,9 cases)and high-grade ESS(HGESS,17 cases).The morphological features of the ESS on MRI were analyzed,and the ESS signal intensity on DWI and ADC value were measured.Immunohistochemical analysis was performed to calculate the Ki-67 index.The t-test was used to compare the ADC values and Ki-67 indexes between the HGESS and LGESS groups,and the Pearson correlation coefficient was used to analyze the correlation between ADC values and Ki-67 indexes.Results All the 26 patients showed either homogeneous or heterogeneous isointensity and hypointensity on T1WI,heterogeneous hyperintensity on T2WI,and hyperinetensity on DWI.The mean ADC of the solid components was lower in the HGESS group[(0.74±0.11)×10^-3mm^2/s]than in the LGESS group[(1.07±0.24)×10^-3mm^2/s](P<0.05).The mean Ki-67 index was higher in the HGESS group(45.53%±14.23%)than in the LGESS group(8.33%±2.50%)(P<0.05).The ADC values were negatively correlated with Ki-67 indexes(r=-0.726,P<0.001).Conclusion The ESS presents certain characteristics on MRI,and the ADC value of tumor can indirectly reflect the pathological grading of ESS.