Intracranial extra-axial ependymoma: a case report

Introduction: DGG, female, 15 years old, from Terra Santa (PA), started a moderate-to-intense, progressive, holocranial headache that had not responded to analgesic, associated with weight loss for 7 months and behavioral change (psychomotor agitation alternated with social isolation). The patient evolved with lowering of the level of consciousness associated with jet vomiting.

Methods: At physical examination, the Glasgow Coma Scale (GCS) was 11 (E = 4, V = 1, M = 6), with no motor or sensory deficits, and preserved cranial nerves. Magnetic resonance imaging showed an extra-axial expansive frontal-temporal lesion on the right, with homogeneous contrast uptake, which led to the suspicion of meningioma. The treatment chosen was microsurgery for intracranial tumor, in which the lesion was bleeding and friable. The lesion was completely excised. Currently, patients are found with grade 3 monoparesis of the upper left limb, and signs of pyramidal release, preserved cranial nerves.

Results: In histopathology, anaplastic ependymoma (WHO Grade III) was identified. Ependymomas account for 1.9% of all primary brain tumors and usually arise from the lining of the ventricular system or the central canal of the spinal cord. Intracranial extra-axial ependymomas (IEAEs) are extremely rare, with only 21 cases reported. IEAEs are extremely rare, defined as extraparenchymal, extraventricular ependymoma, located between the dura mater and the pia mater, without involving the cortex. To the best of our knowledge, we describe the first case report of IEAE in Brazil. The clinical picture is composed of intracranial hypertension, which presents as intense headache, seizure and neurologic focal deficit. In the imaging tests, the ependymoma appears to be isointense to hypointense in T1 and hyperintense in T2 with vascular contrast uptake.

Conclusion: IEAEs are able to mimic the meningioma, as demonstrated by the case, and it should be considered as a differential diagnosis when young patients presenting with images suggestive of meningioma. IEAE is a rare neoplasm with varied clinical and radiological presentations, which can mimic meningiomas. Thus, it should be among the differential diagnoses of images suggestive of meningiomas in young patients.