Preoperative prediction of IDH1 mutation status and Ki-67 expression in glioma using apparent diffusion coefficient parameters

Objective The aim of this study was to investigate the value of magnetic resonance imaging (MRI) - diffusion-weighted imaging (DWI) in predicting IDH1 gene mutation and Ki-67 expression in glioma. Methods Clinical data from 72 patients (Grade II: 25; Grade III: 19; Grade IV: 28) were retrospectively analyzed. Preoperative ADC parameters—including minimum, average, relative minimum, and relative average ADC—were measured. These values were compared across WHO grades and IDH1 genotypes, and correlated with the Ki-67 proliferation index. Results 72 patients with glioma were divided into low-grade cases (Grade II: 25 cases), accounting for 34.72%, and high-grade cases (Grade III: 19 cases, Grade IV: 28 cases), accounting for 65.28%. High-grade gliomas demonstrated significantly lower values across all ADC parameters compared to low-grade gliomas (P < 0.05). Conversely, patients with IDH1 mutant gliomas exhibited significantly higher ADC values than those with IDH1 wild-type tumors (P < 0.05). Correlation analysis revealed that all analyzed ADC values showed negative correlation with the Ki-67 proliferation index; P < 0.05. In terms of the ROC curve analysis results, the relative minimum ADC was the most indicative of an IDH1 mutation, with the largest AUC at 0.889, and an overall sensitivity and specificity of 79.31% and 72.41%, respectively. Conclusion ADC value can be used to evaluate the IDH1 mutation status and Ki-67 expression level of glioma patients before surgery, which is helpful for clinicians to make preoperative classification diagnosis of glioma.