Extramedullary hematopoiesis in a malignant meningioma

An unusual case of malignant intracranial meningioma is presented. The operative management was complicated by the abrupt development of fulminant brain edema and herniation. The tumor contained areas of extramedullary hematopoiesis, a finding not previously reported. Various pathogenetic mechanisms involved in intradural extramedullary hematopoiesis are discussed.