Marginal zone B-cell lymphoma involving a longstanding fibrous meningioma: an initial manifestation of systemic disease.

The combined presence of meningioma and lymphoma involving the dura is exceptionally rare. A 62-year-old woman, radiologically diagnosed with meningioma 14 years prior but never treated, presented with headaches and visual symptoms. Magnetic resonance imaging demonstrated significant growth of the mass. Surgical resection yielded a composite meningioma and marginal zone B-cell lymphoma. Subsequent systemic workup revealed bone marrow involvement. Low-grade lymphomas rarely metastasize to the central nervous system. When they do, it is usually a result of large cell transformation and typically marks a late event in the course of the disease. This case highlights the necessity of adequate sampling of meningiomas and of including low-grade lymphoma in the differential diagnosis of meningiomas with prominent lymphocytic infiltrates. In addition, this case emphasizes that all patients with lymphoma involving the central nervous system, even when low grade, should receive a full systemic workup.