Clear cell meningiomas: A short series of two patients and literature review

Objectives: Clear cell meningiomas comprise <1% of meningiomas and are classified as World Health Organization grade II tumors. Referred to as the meningioma with benign looking histology but aggressive behavior more research is needed to confirm the unique clinical, radiological and prognostic variables that characterize this specific meningioma sub-type.

Methods: We present a short series of two patients with similar clinical features and radiological imaging characteristics whom presented to our unit. Histo-pathological analysis revealed both lesions to be clear cell meningiomas. We conducted a PubMed search of the literature on clear cell meningiomas to evaluate the observed similarities.

Results: In our short series one of our patients was male and the other was female. The mean age of our patients was 54 years. Both of our patients had a history of duration of symptoms of less than 6 months. Radiologically both of our patients had tumors with heterogeneous contrast enhancement and extensive perilesional vasogenic edema and no hyperostosis. One patient had bony erosion intra-operatively. In one patient gross total resection was achieved and in the other subtotal resection was achieved. Both of our patients were referred for adjuvant radiotherapy and had no tumor progression at one year post surgery.

Conclusion: Our short series supports the demographic profile of patients presenting with clear cell meningiomas by having a similar gender distribution but does not support the mean age described in the literature. Our short series supports the radiological features described for this meningioma subtype. Our patient management supports adjuvant radiotherapy as an important factor associated with progression free survival.