胆碱相对水平在胶质瘤术前分级的价值及与细胞增殖活性的相关性研究

目的：探讨Cho相对水平在胶质瘤术前分级的价值及与肿瘤细胞增殖活性的相关性。材料与方法搜集行1H-MRS检查并经病理证实的脑胶质瘤患者58例，分为Ⅰ～Ⅱ级(低级别)、Ⅲ级、Ⅳ级3组，其中Ⅲ～Ⅳ级为高级别胶质瘤。选取肿瘤实质Cho/Cr最大处及对侧正常表现白质为感兴趣区，获得肿瘤实质Cho/NAA、Cho/Cr、rCho/NAA及rCho/Cr值。根据Ki-67标记指数将Ki-67分级定义为阴性(－)、弱阳性(+)、阳性(++)和强阳性(+++)4级。分析不同级别胶质瘤肿瘤实质Cho相对水平各参数的组间差异性并采用受试者特征曲线(ROC)确定诊断阈值。分析Ki-67级别与胶质瘤肿瘤级别、Cho相对水平各参数的相关性。结果Ⅲ级及Ⅳ级胶质瘤实质部分Cho相对水平各参数显著高于Ⅰ～Ⅱ级胶质瘤(P<0.05)，但Ⅲ级与Ⅳ级间无统计学差异性(P>0.05)，高低级别胶质瘤各参数组间有统计学差异性(P<0.05)；区分高低级别胶质瘤的Cho相对水平各指标中，Cho/NAA的诊断准确率最高，为81.0%，诊断界值为3.04，rCho/Cr曲线下面积最大，为0.823。不同级别胶质瘤Ki-67分级存在显著差异性，两者呈显著正相关(r=0.741， P<0.05)。Cho/NAA、Cho/Cr及rCho/Cr与Ki-67分级呈轻度正相关(r分别为0.313、0.444和0.336，P均<0.05)。结论 Cho相对水平可作为反映胶质瘤细胞增殖状态、评价肿瘤恶性程度的指标。

The relative level of choline:the value in the preoperative evaluation of cerebral glioma grading and the correlation with cell proliferation in gliomas

Objective: To investigate the value of the relative level of choline measured by proton magnetic resonance spectroscopy in the preoperative evaluation of cerebral gliomas grading and the correlation with cell proliferation in gliomas. Materials and Methods: Fifty-eight patients with cerebral gliomas confirmed by histopathology were collected. All patients were performed with 1H-MRS. On the basis of the histopathological diagnosis, the patients were classiifed into three groups:gradeⅠ—Ⅱ(low-grade), 25 cases, gradeⅢ, 19, gradeⅣ, 14. Those whose grades wereⅢorⅣwere classiifed into high-grade gliomas group that included 33 cases. The regions of the maximum Cho/Cr value in solid portion of the tumors and the contralateral normal white matter were selected as regions of interest (ROI). The values of Cho/NAA, Cho/Cr, relative Cho/NAA (rCho/NAA) and relative Cho/Cr (rCho/Cr) of ROIs were obtained. Ki-67 grading was defined as follow:labeling index (LI)<5%is negative (-), 5%≤LI<25%is weakly positive(+), 25%≤LI<50%is positive (++), and LI≥50%is strongly positive (+++). The differences of parameters of the relative level of choline among three groups were analyzed, if the parameters of the relative level of choline had no signiifcant difference between gradeⅢandⅣgliomas, we compared the difference between low-grade and high-grade gliomas. The optimum diagnostic thresholds of the parameters were achieved by using receiver operating characteristic curve (ROC), and we calculated the area under the curve (AUC), sensitivity, speciifcity and accuracy. The correlation between Ki-67 grading and glioma grading, and the correlation between Ki-67 grading and parameters of the relative level of choline were analyzed. Result:The Cho/NAA, Cho/Cr, rCho/NAA and rCho/Cr values of solid portions of tumor of gradeⅢand gradeⅣgliomas were signiifcantly higher than that of gradeⅠ—Ⅱgliomas (P<0.05), however, there was no signiifcant difference between gradeⅢand gradeⅣgliomas (P>0.05). There were signiifcant differences between low-grade and high-grade gliomas (P<0.05). In the parameters of the relative level of choline to differentiate high-grade gliomas from low-grade gliomas, the accuracy of Cho/NAA was the highest, which equaled to 81.0%, and the threshold was 3.04. The AUC of rCho/Cr was maximum, which was 0.823, and the threshold and accuracy were 2.70 and 77.6%, respectively. There was signiifcant difference between different grade gliomas in Ki-67 grading, and there was a positive correlation between Ki-67 grading and gliomas grading (r=0.741, P<0.05). Cho/NAA, Cho/Cr and rCho/Cr had positive correlation with Ki-67 grading (r were 0.313, 0.444 and 0.336, respectively, P<0.05). Conclusions:The relative level of choline is a great indicator that can indicate the state of gliomas cell proliferation and evaluate the level of malignant, it is helpful for classiifcation of cerebral gliomas grading before operation.