MRI-based habitat radiomics for preoperatively predicting IDH status in gliomas.

Objective: The intratumoral heterogeneous vascular permeability and cell density of gliomas are associated with IDH mutation status. Therefore, the authors aimed to construct vascular-cellular habitats based on MRI to investigate their correlation with IDH status.

Methods: In this retrospective analysis, 165 patients with pathologically confirmed glioma who underwent preoperative contrast-enhanced T1-weighted imaging and diffusion-weighted imaging (DWI) at three hospitals were included. Four spatial habitats (subregions) based on contrast-enhanced T1-weighted and DWI-derived apparent diffusion coefficient (ADC) images were defined using K-means voxel-wise clustering. The sensitive habitat of IDH mutation was identified and radiomic features were extracted and screened from the whole tumor and the four habitats. Logistic regression classifiers were used to construct predictive models for IDH mutation.

Results: Of the included patients, 109 (mean age 50.78 years) were assigned to the training set and 56 (mean age 48.21 years) to the external test set. The high contrast enhancement (CE)-high ADC subregion was determined as the sensitive habitat. The four habitats model achieved an area under the receiver operating characteristic curve (AUC) of 0.716 (95% CI 0.553-0.879) in the external test set, indicating better performance than that of the traditional whole tumor model (AUC 0.619, 95% CI 0.446-0.792). Model performance was further improved when focusing on the sensitive habitat, for which the external test set AUC was 0.817 (95% CI 0.676-0.958).

Conclusions: MRI habitat analysis based on contrast-enhanced T1-weighted and DWI sequences had high prediction capabilities for glioma IDH mutation status, which could be used to refine individualized treatment regimens for patients with glioma.