Dural Tail Sign and Middle Meningeal Artery Hypertrophy in Glioblastoma: A Rarity?

Background: Dural tail sign and increased caliber of branches of the external carotid artery (ECA) are common findings in meningioma and they have been rarely reported in intra-axial lesions. Anyway, some cases of glioblastoma (GBM) are reported in the literature, mostly superficially localized, characterized by these 2 findings and therefore, misdiagnosed with meningioma. The aim of this study is to verify the prevalence of dural tail sign and hypertrophy of middle meningeal artery (MMA) in a large cohort of GBMs. Methods: 180 GBM patients were retrospectively evaluated. Deep or superficial localization of GBM was established and the presence of dural tail sign and hypertrophy of the ipsilateral MMA were assessed. The rate of tumor necrosis and the incidence of dural metastases during the radiological follow-up were also evaluated. Inter-rater reliability was calculated using Cohen's K-test. Results: Dural tail sign and enlarged MMA were evident in 30% and 19% of 96 superficial GBM, respectively. Deep GBM did not present those signs. Only one patient developed dural metastasis at follow-up and no differences in terms of tumor necrosis and hypoxic biomarkers expression were evident among GBMs with and without dural and vessel signs. Conclusions: Dural tail sign and hypertrophy of the MMA in superficial GBM are more common than expected. They probably represent reactive rather than a neoplastic infiltration. Knowing these radiological signs may be important in terms of neurosurgery planning and avoiding excessive bleeding. Anyway, this hypothesis should be confirmed by a prospective neurosurgery studio.