Apparent Diffusion Coefficient Histogram Analysis:Differentiation of Genetic Subtypes of Diffuse Lower-grade Gliomas / 中国医学科学院学报

ABSTRACT

To explore the utility of apparent diffusion coefficient(ADC)histogram analysis for differentiating genetic subtypes of diffuse lower-grade gliomas. A total of 55 patients with WHO grade Ⅱ/Ⅲ diffuse lower-grade gliomas who underwent preoperative routine brain magnetic resonance imaging and diffusion weighted imaging in our center were retrospectively evaluated.Among whom there were 14 patients with isocitrate dehydrogenase(IDH)wild-type gliomas(IDH group),19 patients with IDH-mutant 1p19q intact gliomas(IDH 1p19q group),and 22 patients with IDH-mutant 1p19q co-deleted gliomas(IDH 1p19q group).The whole-lesion ADC values derived from histogram analysis(including ADC,ADC,ADC5%,ADC10%,ADC25%,ADC50%,ADC75%,ADC90%,ADC95%,ADC,mode,range,skewness,kurtosis,standard deviation,inhomogeneity,and entrophy)were measured for each patient.All parameters between the different genetic subtypes were compared by using the Student's test or Mann-Whitney test.Receiver operating curve(ROC)analysis was used to assess the diagnostic performance of ADC histogram in distinguishing the different genetic subtypes. Compared with IDH group,the ADC75%(=0.021),ADC90%(=0.015),ADC95%(=0.014),ADC (=0.035),range(=0.009),standard deviation(=0.001)and inhomogeneity(=0.001)were significantly lower in IDH group;in contrast,the ADC (=0.031)and kurtosis(=0.020)of IDH group were significantly higher than those in IDH group.The ADC(=0.010),ADC5%(=0.016),ADC10%(=0.012),ADC25%(=0.007),ADC50%(=0.005),ADC75%(=0.015),and mode(=0.002)were significantly higher in IDH 1p19q group than in IDH 1p19q group.Inhomogeneity achieved the highest area under ROC(AUC)(0.811)in differentiating IDH gliomas and IDH gliomas,with a cutoff value of 0.229;the sensitivity and specificity were 85.7% and 73.2%.The mode achieved the highest AUC(0.744)in differentiating IDH 1p19q gliomas and IDH 1p19q gliomas,with a cutoff value was 1448.75×10 mm /s;the sensitivity and specificity were 57.9% and 90.9%. ADC histograms analysis may be helpful to differentiate genetic subtypes in lower-grade gliomas.