Histologic Evidence for Arteriovenous Malformation-Like Vasculature Occurring within an Intracerebral Schwannoma: A Case Report and Review of the Literature

CT and MRI findings of intra-parenchymal and intra-ventricular schwannoma: a series of seven cases

Objective

To analyze the computed tomography (CT) and magnetic resonance imaging (MRI) features of patients with intra-parenchymal and intra-ventricular schwannoma.

Methods

The CT and MRI features of seven cases with intra-parenchymal and intra-ventricular schwannoma were analyzed retrospectively.

Results

There were four men and three women (median age, 25 years; range, 12–42 years) in this study. The median tumor size was 4.4 cm (range, 3.1–6.5 cm). The mass was, respectively, round in four cases (57.1%), lobulated in two cases (28.6%) and oval in one case (14.3%). All tumors were well-circumscribed. Septa in the mass could be observed in three cases (42.9%), and nodular calcification was observed in two cases (28.6%), which peritumoral edema (n = 3, 42.9%) and hydrocephalus (n = 3, 42.9%) could be observed. Most of these lesions (n = 6) presented iso-hypointensity on T1-weighted images and iso-hyperintensity on T2-weighted images, except one lesion showing low intensity on T2WI. In addition, a fluid–fluid level was observed in one case. After contrast agents’ injection, all masses illustrated heterogeneously moderate to marked enhancement.

Conclusions

A well-defined solid and cystic mass with calcification and moderate to marked delayed enhancement may be an objective account of intra-parenchymal or intra-ventricular schwannoma.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12880-022-00917-z.

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.

Intracerebral schwannoma: A case report and literature review

Intracranial schwannoma accounts for between 5 and 8% of intracranial tumors, whereas intracerebral schwannoma, a rare disease, accounts for <1% of intracranial schwannomas. In addition to the present case report, a total of 84 cases reported within China and elsewhere were reviewed and summarized, and the age of the tumor onset, the site of disease, imaging results, clinical presentation, pathological classification and prognosis were analyzed. The present case report described a 12-year-old female with an intracerebral schwannoma in the brainstem, who was followed-up for 5 years using magnetic resonance imaging after a surgical resection without recurrence, and clinical symptoms were reported to have completely resolved. The incidence of intracerebral schwannoma was low among cases, and the correct diagnosis was not able to be made preoperatively, and the majority of cases were diagnosed on the basis of postoperative pathology. The majority of cases analyzed were supratentorial, occurring at an age ≤40 according to previous literature. In addition, 33% of patients presented with subtentorial schwannoma, occurring at an age >40. The prognosis was classified as good (patient can live independently) for the majority of patients if surgery was able to completely resect the lesion.