Supratentorial convexity schwannoma unrelated to cranial nerves: Case report and review of the literature

Background: Intracranial schwannoma not related to cranial nerves is rare entity, and difficult to be diagnosed preoperatively. Here, we experienced a case of convexity schwannoma mimicking convexity meningioma, and discuss about the characteristics of such cases based on the past published reports. Case Description: A 48-year-old man presented with a sudden onset of seizures. Brain magnetic resonance image (MRI) revealed a small mass lesion in the peripheral aspect of the right parieto-frontal lobe. The mass was isointense on T1-weighted and hyperintense on T2-weighted MRI, with homogenous enhancement after contrast medium administration. After the feeder embolization on the previous day, removal of the tumor was performed. The tumor revealed a well-demarcated, firm, spherical tumor beyond, and beneath the dura and was relatively easy to be separated from the brain. Histologically, the tumor was observed to be in subarachnoid space extending to outer space of dura-mater, intimately attached to the pia mater. The histological diagnosis was schwannoma. Conclusion: In our case, MRI findings are similar to convexity meningioma; however, the pathological diagnosis was schwannoma. Cerebral convexity is an extremely rare location for schwannoma. We emphasize that schwannoma, not related to cranial nerves, may arise in the subdural convexity space.

Seizures and Blurred Vision as Initial Presentation of Intracerebral Schwannoma: A Rare Tumor of the Brain

Schwannomas are the most common tumor of peripheral nerves which are arising from Schwann cells and are benign in their nature. Intracranial schwannoma accounts for between 5 and 8% of intracranial tumors, whereas intracerebral schwannoma, a rare disease, accounts for <1% of intracranial schwannomas. Intracerebral schwannoma has no specific clinical manifestation, and it is not classified by age. Here, we are reporting a case of an 18-year-old male who presented with attacks of seizures. MR imaging studies were done and showed right parieto-occipital cortical and subcortical mass lesion with intense enhancement and significant vasogenic oedema with mass effect on the subjacent sulci. The tumor was surgically removed through a right occipital craniotomy. Histological findings confirmed the diagnosis of schwannoma.

Value of SSTR2A and Claudin - 1 in Differentiating Meningioma from Schwannoma and Hemangiopericytoma

BACKGROUND: The distinction between meningioma, schwannoma and solitary fibrous tumour/ hemangiopericytoma can be challenging in some cases. This study evaluates the expression of Somatostatin receptor 2A (SSTR2A) and Claudin-1 in these different tumours.MATERIAL AND METHODS: Thirty-five cases of meningioma, 10 cases of intracranial schwannoma and 10 cases of hemangiopericytoma were assessed. The immunohistochemical expression of SSTR2A and Claudin-1 was evaluated and scored according to the percentage of immunostained tumour cells (0: 1+, 2+ and 3). The intensity of staining was classified as weak, moderate and strong.RESULTS: Positivity for SSTR2A and Claudin-1 was encountered in 89% and 49% of meningiomas respectively. None of the schwannomas or hemangiopericytomas was positive for any of both markers. All grade I and II meningiomas were positive for SSTR2A, and only 20% of grade III showed positive staining (p < 0.05). Claudin-1 positivity was detected in 50%, 43% and 60% of grade I, II and III meningioma respectively, with significantly higher intensity in grade III (p < 0.05).CONCLUSION: SSTR2A is highly sensitive and specific for meningioma. Claudin-1 is highly specific for meningioma, with low sensitivity. The adjunctive use of both markers can be very helpful in the diagnosis of meningioma and its distinction from schwannoma and hemangiopericytoma.

Cystic Trigeminal Schwannoma. Case presentation

Trigeminal schwannoma is the second commonest intracranial schwannoma; they remain rare. A minority exhibit cystic changes, with even fewer an intracystic fluid level. We report a case of a 45-year-old man, presented with a progressive hearing loss, worsening right-sided facial spasms and facial numbness in the region of the right trigeminal nerve. Neurological examination revealed hypoesthesia in the right facial region and intermittent rights sided hemi-facial spasms, without signs of raised intracranial pressure or achieve the mixed nerves or neurological deficit. A Magnetic resonance imaging of the brain revealed a cystic mass in the right cerebello-pontine angle with extension forward towards the cavum meckel. The patient was operated by retro sigmoid approach, with a total resection of the tumor. Intracranial cystic schwannomas constitute an uncommon subset of tumors with a distinct clinico-biological behavior. The presence of fluid–fluid levels within the tumors, although rare, confirms the cystic nature of the neoplasms. Cystic areas are usually secondary to the coalescence of mucinous or microcystic regions in Antoni B tissues. The treatment is surgical in the majority of cases and stereotactic radiosurgery has a clear role for adjuvant treatment of post-surgical recurrence of the tumor or residue.