Epithelioid schwannoma of the vestibular nerve

TC Tan, PWY Lam
Correspondence: Dr T C Tan, tzechingtan@hotmail.com

ABSTRACT
Epithelioid schwannomas are rarely encountered intracranially, with only four cases involving the eighth nerve reported in the literature. Histological behaviour ranging from benign to aggressive has been described. We report a 45-year-old woman who presented with right-sided tinnitus and hearing impairment. Magnetic resonance imaging revealed a tumour in the right cerebellopontine angle with intracanalicular extension. The patient underwent retromastoid craniectomy with near-total tumour excision. Microscopical examination confirmed the diagnosis of epithelioid schwannoma of the vestibular nerve. Intraoperative findings of sharp circumscription, bland histological appearance, low proliferative activity, coupled with the indolent clinical course, point to the quiescent nature of the lesion in this case.

Keywords: acoustic nerve, epithelioid schwannoma, immunohistochemistry, magnetic resonance imaging, vestibular tumour
Singapore Med J 2004; 45(8): 393-396