Metastatic high-grade meningioma: A case report and review of risk factors for metastasis

Abstract Meningiomas are the most common primary tumor of the CNS, and although they usually have a good prognosis, meningiomas can metastasize to extracranial sites, greatly worsening the prognosis. Due to its infrequency, the clinical and molecular risk factors associated with this event are poorly characterized in the literature. A 69-year-old man was found to have a meningioma in the left parieto-occipital parafalcine region. Over the subsequent decade, the patient experienced multiple local tumor recurrences, including with invasion through the scalp and superior sagittal sinus. The tumor was WHO grade 2-3 and next-generation sequencing was notable for TERT promoter mutation, homozygous deletion of CDKN2A, and high variant allele frequency of NF2. The tumor metastasized to the axial and appendicular skeleton, liver, kidney, and lung, and the patient ultimately succumbed to disease. In summary, this is the first report of multiple simultaneous and anatomically-distinct extracranial metastases from a primary intracranial meningioma.