Supratentorial diffuse astrocytic tumours: proposal of an MRI classification

Abstract

The aim of this study was to obtain an MRI severity-related classification of diffuse astrocytic tumours able to integrate the histological data in the grading of such tumours. We studied presurgical MR images of 91 patients with a histological diagnosis of astrocytoma, anaplastic astrocytoma and glioblastoma. A score ranging from 1 to 3 was assigned by two independent readers to each of the following MR features: oedema, mass effect, contrast enhancement, borders, signal homogeneity, necrosis, haemorrhage and flow void. Statistical analysis showed significant differences in the mean MRI scores between the three histological grades. Contrast enhancement was found to be the best predictor of the histological grade followed by necrosis, signal homogeneity and border scores. This classification represents a simple and reproducible means of carefully evaluating some macroscopic characteristics of these tumours. It could be used to integrate histological data especially in cases in which tissue sampling defects may affect the validity of this examination.

Magnetic Resonance Imaging Characteristics Predict Epidermal Growth Factor Receptor Amplification Status in Glioblastoma

“…Several studies found that MRIs of glioblastomas showed more hemorrhage, cyst formation, necrosis, and contrast enhancement than those of low-grade and anaplastic astrocytomas (18,19). The present report suggests that, with further volumetric analysis, a preoperative MRI may also enable prediction of molecular glioblastoma subtype.…”

Grading diffuse gliomas without intense contrast enhancement by amide proton transfer MR imaging: comparisons with diffusion- and perfusion-weighted imaging

“…Traditionally, the presence and degree of contrast enhancement (CE) after the administration of a gadolinium-based contrast agent on MR imaging have been used as characteristics of the malignancy of diffuse gliomas [4,5]. Typically, HGGs show moderate-to-strong CE, whereas LGGs exhibit no or mild CE.…”

Preoperative Grading of Presumptive Low-Grade Astrocytomas on MR Imaging: Diagnostic Value of Minimum Apparent Diffusion Coefficient

“…The typical MR imaging features of low-grade astrocytomas include a relatively well-defined usually homogeneous mass that displays little or no mass effect, with minimal or no vasogenic edema and little or no enhancement after contrast administration. [5][6][7] Nevertheless, it is not always easy to differentiate low-grade astrocytomas from high-grade ones on the basis of conventional MR imaging findings. It has been reported that high-grade and low-grade astrocytomas can have overlapping features on MR imaging.…”