磁共振征象评估间变性星形细胞瘤异柠檬酸脱氢酶-1突变状态的研究

Magnetic resonance imaging assessment of isocitrate dehydrogenase 1 mutation status in degenerative astrocytoma

目的分析对比间变性星形细胞瘤异柠檬酸脱氢酶-1(isocitrate dehydrogenase1,IDH-1)突变型和IDH-1野生型的MRI影像学特征。材料与方法选取手术及病理证实的45例间变性星形细胞瘤,其中IDH-1突变型20例,IDH-1野生型25例,所有病例均行MRI常规序列T1WI、T2WI、FLAIR、DWI及T1WI增强扫描。对肿瘤的发病性别、年龄、部位、病变个数、肿瘤边界、囊变坏死、出血、肿瘤最大径、水肿最大径、强化程度及最小表观扩散系数值(mADC)、标准化最小表观系数(rmADC)等征象与指标分别进行统计分析。结果间变性星形细胞瘤中IDH-1突变型好发于右侧额叶,IDH-1野生型好发于左侧额叶,两组间有统计学差异(P<0.05)。IDH-1突变型者囊变坏死占45%,野生型者占75%,两组间有统计学差异(P<0.05)。强化程度为无强化、轻度强化、中度强化、重度强化者IDH-1突变型分别占比25%、50%、20%、5%,IDH-1野生型分别占比8%、12%、52%、28%,两组间有统计学差异(P<0.05)。IDH-1突变型肿瘤最大径[(50.01±19.11) mm]小于IDH-1野生型[(64.58±11.52) mm]。IDH-1突变组mADC值均值为(1.17±0.20)×10^-3mm^2/s,IDH-1野生组mADC值均值为(0.84±0.14)×10^-3mm^2/s;IDH-1突变组rmADC值均值为(0.16±0.04)×10^-3mm^2/s,IDH-1野生组rmADC值均值为(0.13±0.02)×10^-3mm^2/s,两组间有统计学差异(P<0.05)。两组患者的发病性别、年龄、病变个数、肿瘤边界、是否伴有出血、水肿最大径等征象无统计学意义(P>0.05)。结论间变性星形细胞瘤的发生部位、囊变坏死率、强化程度、肿瘤最大直径、mADC值、rmADC 值可用来术前评估间变性胶质瘤的IDH-1突变状态,进而指导临床采用个体化治疗方案及预后评估。

Objective:To analyze the MRI features of the isocitrate dehydrogenase 1 (IDH-1) mutant and the IDH-1 wild type of the anaplastic astrocytoma.Materials and Methods:Forty-five cases of anaplastic astrocytoma con firmed by surgery and pathology were selected,including 20 cases of IDH-1 mutation and 25 cases of IDH-1 wild type.All cases underwent conventional MRI sequence enhanced T1WI,T2WI,FLAIR,DWI and T1WI.The sex,age,location,number of lesions,tumor boundary,cystic degeneration and necrosis,hemorrhage,tumor maximum diameter,edema maximum diameter,enhancement degree,minimum apparent diffusion coefficient (mADC) value,ratio of mADC (rmADC) were statistically analyzed.Results:In the anaplastic astrocytoma,the IDH-1 mutant appeared in the right frontal lobe,and the IDH-1 wild type occurred in the left frontal lobe.There was a statistical difference between the two groups (P<0.05).The IDH-1 mutant had cystic necrosis accounted for 45%,and the wild type accounted for 75%.There was a statistically signi ficant difference between the two groups (P<0.05).The degree of enhancement was non-enhanced,mildly enhanced,moderately enhanced,and severely enhanced.The IDH-1 mutants accounted for 25%,50%,20%,and 5%,respectively,and the IDH-1 wild type accounted for 8%,12%,and 52%,respectively.28%,there was a statistical difference between the two groups (P<0.05).The maximum diameter of the IDH-1 mutant tumor (50.01±19.11 mm) was smaller than that of the IDH-1 wild type (64.58±11.52 mm).The mean value of mADC in IDH-1 mutation group was (1.17±0.20)×10^-3mm^2/s,the mean value of mADC in IDH-1 wild group was (0.84±0.14)×10^-3mm^2/s;the mean value of rmADC in IDH-1 mutation group was (0.16±0.04)×10^-3mm^2/s,the mean value of rmADC in IDH-1 wild group was (0.13±0.02)×10^-3mm^2/s,and there was statistical difference between the two groups (P<0.05).There was no significant difference between the two groups in sex,age,number of lesions,tumor margin,presence or absence of hemorrhage or edema (P>0.05).Conclusions:The occurrence of anaplastic astrocytoma,the rate of cyst necrosis,the degree of enhancement,the maximum diameter of the tumor,the mADC value,and the rmADC value can be used to evaluate the IDH-1 mutation status of the anaplastic glioma before surgery,and then guide the clinical individualized treatment plan.And prognosis assessment.