Supratentorial Cystic Meningioma Resembling Pilocytic Astrocytoma: A Case Series and Literature Review

Cystic meningiomais a rare subtype of meningioma. Various brain tumors may mimic cystic meningioma in imaging appearances.

Herein, we reported a series of cases with cystic meningiomas primarily misdiagnosed as pilocytic astrocytoma due to a similar radiological appearance.

This case-series study included 20 patients with cystic meningiomas admitted to the Ghaem Hospital, Mashhad, Iran, between 2012 and 2019. The findings of magnetic resonance imaging (MRI), computed tomography, and neurological examination were recorded preoperatively. All patients underwent surgery, and biopsies were obtained, confirming the histopathological diagnosis of thetumor.

The patients’ mean age was obtained at 40.7±12.5 years, and 11 and 9 subjects were men and women, respectively. Most of the patients presented with headaches (50.0%), and hemiparesis (60.0%) was the most found in the neurological examination. The results of all neuroimaging studies revealed solid-cystic supratentorial tumors, in which cysts were intratumoral, larger than solid components, and eccentric relative to them. Most of the cysts were located in the frontal lobe. The signal intensity of T2-weighted MR images showed hypointense lesions in 25.0% of the cases; however, 45.0% of the patients were hyperintense and 30.0% of them were isointense to grey matter. After contrast injection, the tumor’s solid and periphery experienced a homogeneous enhancement. The most common histopathological finding was meningothelial cells (30.0%) followed by fibroblastic cells (25.0%).

Cases with an initially diagnosed pilocytic astrocytoma in the imaging can turn out to show cystic meningioma after pathological assessments, which deserves clinicians’ notice