Recurrent Extracranial Meningioma with Transformation to Higher Grade (Atypical Meningioma) Diagnosis by Cytology

Sudha A, Power R, Raju KVVN

Abstract

Meningiomas comprise 13-19% of primary intracranial neoplasms. They may be found extracranially in sites such as the middle ear, temporal bone, sinonasal cavity, orbit, oral cavity, parotid gland and soft tissue of head and neck. They are called "secondary" if a connection to the CNS is demonstrated. Tumor recurrence may be accompanied by dedifferentiation from a more benign histology and is known to occur in tumors which had gross total resection. Histology, proliferative activity and ploidy studies help in prognostication of natural history of disease, identifying tumors with aggressive behaviour and predicting recurrence, in addition to diagnosis and grading. The case presented here had a benign extracranial meningioma in the left preauricular region with MIB 1 score less than 1 which was excised completely. Recurrence developed at the same site after 1 year and three months associated with atypical cytologic features and extensive intracranial spread. Comparison of FNA pattern in primary and recurrent meningiomas revealed progression of benign meningioma to a higher grade, thereby helping the clinician in effective management.

Journal of Cytology : 2004; 21 (4) : 207-210

Key Words : Extracranial, Atypical meningioma, FNA