Abstract: To provide guidance to clinical diagnosis and develop individual-based treatment/prognostic evaluation, this study explored the correlations between morphological characteristics of glioblastoma (GBM) measured by conventional MRI and expression levels of GBM-specific molecular biomarkers. MRI data of 60 patients with histopathologically confirmed GBM were analyzed retrospectively, from which the morphological characteristics of GMB (i.e., TLD, ELD and CTE/TLD ratio) were measured. Histochemical staining was used to measure the levels of GBM-specific molecular biomarkers (i.e., EGFR, IDH-1, TP53, PTEN and NEFL), which were calculated as the product of staining index and stained area. Correlations among the morphological characteristics and the levels of molecular biomarkers were assessed using multivariate logistic regression analyses. There was a significant correlation between TLD and EGFR level (r=0.796). The correlation between TLD and PTEN level was positive (r=0.533), while the correlation between TLD and IDH-1 level was negative (r=-0.672). CTE/TLD had a positive correlation with EGFR (r=0.622) and PTEN (r=0.638) levels, along with a negative correlation with IDH-1 level (r=-0.493). ELD had no significant correlation with the levels of all five molecular biomarkers. It was concluded that the morphological characteristics of GBM derived from conventional MRI had correlations with the expression levels of EGFR, IDH-1 and PTEN, and it was possible to derive heterogeneity, molecular classification and prognosis of GBM using conventional MRI.

Key words: MRI, GBM grading, conventional imaging, GBM-specific molecular biomarker