Intraparenchymal Meningioma, A Challenging Diagnosis: Case Report

Case Report

Austin J Med Oncol. 2023; 10(1): 1074.

Intraparenchymal Meningioma, A Challenging Diagnosis: Case Report

Khansa Abderrahmen*; Wiem Mansour; Alaa Belhaj; Mohamed Nidhameddine Kchir; Jalel Kallel

Department of Neurosurgery, National Institute Mongi Ben Hmida of Neurology of Tunis, Faculty of Medicine of Tunisia, Tunisia El Manar University, Tunisia

*Corresponding author: Khansa Abderrahmen Department of Neurosurgery, National Institute Mongi Ben Hmida of Neurology of Tunis, Road Jabari 1007, Rabta, Tunisia Tel: 0021699925418 Email: [email protected]

Received: May 19, 2023 Accepted: June 15, 2023 Published: June 22, 2023


Background: Primary intraparenchymal meningiomas are extremely rare; their similarities to other intra-axial lesionsand thelack of dural adhesion make their presurgical diagnostic approach challenging.

Case Description: A 27-year-old male, with no past medical history, presented to our emergency department for a first time grand mal seizure. Magnetic resonance imaging evidenced a 1,6×1,2 cm mass in the right temporo-parietal region. It was iso intense on T1WI, hyper intense on T2 WI, surrounded by large vasogenic edema and homogeneously enhanced on contrast magnetic resonance imaging with diffusion restriction. During surgery, the tumor was found to be located within the parenchyma with no dural attachment. It was removed en bloc. Histopathological examination confirmed the positive diagnosis of transitional meningioma (WHO Grade I).

Conclusion: Intraparenchymal meningiomas are rarely reported in the literature. Their preoperative diagnosis is extremely difficult to make. Histopathological examination plays a key role for an accurate diagnosis.

Keywords: Meningioma; Intraparenchymal meningioma; Subcortical meningioma; Meningioma without dural attachment


Meningiomas are typically extra axial lesions originating from the arachnoid cap and meningothelial cells present in the arachnoid layer of the meninges or Pacchionian granulations. They classically display dural attachment and easily diagnosed by CT and MRI [1].

Intra-axial meningiomas are extremely rare, their unusual intraparenchymal siteand the lack of dural adhesion make the presurgical diagnostic approach challenging [1]. Herein we report an unusual case of intraparenchymal meningioma that was not evocated preoperatively.

Case Report

A 27-year-old right-handed man presented to our emergency department for a first time grand mal seizure. This incident was described by the family as a generalized tonic clonic event lasting about 4 minutes with tongue biting and involuntary passing of urine after which he persisted irresponsive and confused during thirty minutes. The patient had no prior medical history, no history of tobacco, alcohol or other substance use and no prior head trauma. The physical examination was unremarkable; there were no focal neurological findings and no papilledema on fundus. Routine blood tests were within normal limits. An emergent CT scan of the head with no contrast enhancement (Figure 1) showed an extensive low-density area in the right temporo-parietal white matter extending in a finger-like fashion. A subsequent MRI of the head (Figure 2) evidenced a right temporo-parietal subcortical lesion surrounded by large vasogenic edema. The mass, measuring 1,6×1,2 centimeters, is iso intense on T1 MRI, hyper intense on T2 MRI with diffusion restriction. After administration of Gadolinium, a homogeneous uptake of the entire lesion is noted. The first evocated diagnosis was a solitary brain metastasis. Surgical resection of the mass was planned. During operation, a standard right temporo-parietal craniotomy was performed, intraoperative findings confirmed that the dura mater was intact and the tumor was located within the parenchyma (Figure 3). It was clearly demarcated and dissected from the surrounding brain parenchyma and removed en bloc. The patient made an uneventful postoperative recovery. The histopathological examination of the tumor showed features compatible with a transitional meningioma, World Health Organization (WHO) grade I. Immunohistochemical study revealed positive staining of the tumor cells for Vimentin, S-100 and epithelial membrane antigen EMA (Figure 4). Tumor cells were negative for Smooth Muscle Actin (SMA) Glial Fibrillary Acid Protein (GFAP) and Cytokeratin 7. The Ki 67 labeling index was less than 1%.