Extracranial Clear Cell Meningioma in Neck: Report of a Rare Case with Diagnostic Challenge to the Cytopathologist - Abstract
Extracranial clear cell meningioma is a rare, distinctive and intrinsically aggressive subset of meningioma affecting younger females. The early recognition of this variant is important as it is associated with a high recurrence rate & mortality. We present a case of a 27 year old female who presented with a swelling in the right infra-auricular region. Fine Needle Aspiration Cytology (FNAC) showed pattern less sheets and focal acinar clusters of polygonal cells with vacuolated cytoplasm. A wide differential diagnosis was considered (metastatic renal cell carcinoma, nodular hidradenoma, acinic cell carcinoma, oncocytoma, parathyroid adenoma & sweat gland carcinoma). A clinico-radiological & histopathological correlation was advised. Biopsy showed sheets & whorls of clear round to ovoid cells which were positive for CK, EMA, Vimentin and NSE. Computed tomography scans were reviewed and showed an intracranial extension of the lesion. Based on the above features, a diagnosis of clear cell meningioma was made. This case highlights the need for incorporating clear cell meningioma as a differential diagnosis whenever a clear cell epithelial neoplasm is encountered on FNAC, considering each differential has a distinctive behaviour, treatment protocol and prognosis.