We present two cases of clear cell meningioma (CCM) in the intracranial and intraspinal region with anaplastic features. On histological examination, both the tumors exhibited unusual anaplastic appearances with nuclear pleomorphism, a high mitotic activity and necrosis, which were different from classical CCMs. The tumor cells were immunoreactive to epithelial membrane antigen (EMA) and vimentin with a high MIB-1 index of 40%. Total excision of the tumors was performed in both cases. The male patient was found to have local recurrence and lateral ventricle metastasis 3 months after the total excision. We reviewed the clinicopathological features, disagnosis and prognosis of the disease. We recommend that postoperative adjuvant radiotherapy or chemotherapy be performed after total tumor excision, and MRI scan every 3-6 months is mandatory during the initial follow-up period.
Adult ; Aged ; Female ; Follow-Up Studies ; Humans ; Male ; Meningeal Neoplasms ; immunology ; pathology ; therapy ; Meningioma ; immunology ; pathology ; therapy ; Mucin-1 ; immunology ; Vimentin ; immunology