Invasive intracerebral schwannoma mimicking meningioma in a child.

METHODS

An 8-year-old boy presented to the emergency department after a generalized tonic-clonic seizure that lasted for 5 min. Magnetic resonance imaging showed a 2x2 cm, intraaxial, contrast-enhanced cortical lesion in the posterior right frontal lobe. On several images the lesion appeared to be dural-based and was presumed to be a meningioma. The patient was placed on dilantin and returned 1 month later for elective surgical resection.

RESULTS

At surgery, a rim of intact pia was identified between the dura and the tumor. Although initial frozen-section analysis was consistent with meningioma, subsequent immunohistochemical staining and review at an outside institution established the diagnosis of intracerebral schwannoma. The patient's postoperative course was uncomplicated and he remains seizure-free with no sign of recurrence at 18 months.

CONCLUSIONS

Intracerebral schwannomas are uncommon cortical lesions in children. Imaging characteristics alone can be misleading; neuropathological support is essential for accurate diagnosis.