Purely cystic meningioma: Case report and systematic review of the literature.

Meningiomas are the most common benign intracranial tumors. They are generally asymptomatic, and discovered incidentally during cerebral imaging. The vast majority of meningiomas are solid, highly cellular and well-vascularized neoplasms. However, in several cases, they can be partially or, even rarely, almost completely cystic making their differential diagnosis and management challenging. In this paper, we present the rare case of a 59-year-old female patient, presenting with persistent headaches, who was diagnosed with a left parieto-occipital purely cystic lesion. The patient underwent a complete resection of this cystic lesion because of increasing headaches and volumetric progression. Interestingly, the histological assessment confirmed a cystic WHO grade I meningioma. The evolution was favorable and there was no recurrence after 3 years of follow-up. We also perform a systematic review of the literature concerning purely cystic meningiomas and we discuss the particular histological features of cystic meningiomas as well as the possible pathogenesis. This challenging clinical entity can easily be misdiagnosed as hemangioblastoma or glial/metastatic tumor with cystic component.