Prediction of Ki-67 labeling index, ATRX mutation, and MGMT promoter methylation status in IDH-mutant astrocytoma by morphological MRI, SWI, DWI, and DSC-PWI

ObjectiveNoninvasive detection of molecular status of astrocytoma is of great clinical significance for predicting therapeutic response and prognosis. We aimed to evaluate whether morphological MRI (mMRI), SWI, DWI, and DSC-PWI could predict Ki-67 labeling index (LI), ATRX mutation, and MGMT promoter methylation status in IDH mutant (IDH-mut) astrocytoma.MethodsWe retrospectively analyzed mMRI, SWI, DWI, and DSC-PWI in 136 patients with IDH-mut astrocytoma.The features of mMRI and intratumoral susceptibility signals (ITSS) were compared using Fisher exact test or chi-square tests. Wilcoxon rank sum test was used to compare the minimum ADC (ADC(min)), and minimum relative ADC (rADC(min)) of IDH-mut astrocytoma in different molecular markers status. Mann-Whitney U test was used to compare the rCBV(max) of IDH-mut astrocytoma with different molecular markers status. Receiver operating characteristic curves was performed to evaluate their diagnostic performances.ResultsITSS, ADC(min), rADC(min), and rCBV(max) were significantly different between high and low Ki-67 LI groups. ITSS, ADC(min), and rADC(min) were significantly different between ATRX mutant and wild-type groups. Necrosis, edema, enhancement, and margin pattern were significantly different between low and high Ki-67 LI groups. Peritumoral edema was significantly different between ATRX mutant and wild-type groups. Grade 3 IDH-mut astrocytoma with unmethylated MGMT promoter was more likely to show enhancement compared to the methylated group.ConclusionsmMRI, SWI, DWI, and DSC-PWI were shown to have the potential to predict Ki-67 LI and ATRX mutation status in IDH-mut astrocytoma. A combination of mMRI and SWI may improve diagnostic performance for predicting Ki-67 LI and ATRX mutation status.

Automated summary

This study aimed to evaluate the predictive value of mMRI, SWI, DWI, and DSC-PWI for Ki-67 LI and ATRX mutation status in IDH-mut astrocytoma. The results showed that these imaging modalities could accurately predict Ki-67 LI and ATRX mutation, with a possible improvement in diagnostic performance by combining mMRI and SWI.