An unusual case of primary leptomeningeal marginal zone B-cell lymphoma

Primary leptomeningeal lymphomas are rare, and usually follow a rapid clinical course with early systemic involvement. A 60-year-old woman presented with a 3-year history of worsening seizures and memory loss. Neuroimaging showed widespread meningeal calcification. After extensive investigations a meningeal biopsy revealed a low-grade B-cell lymphoma categorized as an extranodal marginal zone B-cell lymphoma, attributed to the same histological group as the MALT (mucosa-associated lymphoid tissue) lymphomas described in the stomach, thyroid, salivary glands and orbit. There was no evidence of systemic involvement. The extensive meningeal calcification would appear to be a novel finding in primary leptomeningeal lymphoma whereas the unusually long clinical history in this case is possibly related to the particular histological type of low-grade B-cell lymphoma.