Case report: Primary intracranial mucosa-associated lymphoid tissue lymphoma presenting as two primary tumors involving the cavernous sinus and extra-axial dura, respectively.

Primary intracranial mucosa-associated lymphoid tissue (MALT) lymphoma is a rare type of brain tumor, with only a few reported cases worldwide that mostly have only one lesion with conventional magnetic resonance imaging (MRI) findings. Here, we present a special case of intracranial MALT lymphoma with two mass lesions radiographically consistent with meningiomas on MRI before the operation. A 66-year-old woman was admitted to the hospital with intermittent right facial pain for 1 year, aggravated for the last month. Brain MRI showed two extracerebral solid masses with similar MR signal intensity. One mass was crescent-shaped beneath the skull, and the other was in the cavernous sinus area. Lesions showed isointensity on T1WI and T2WI and an intense homogeneous enhancement after contrast agent injection. Both lesions showed hyperintensity in amide proton transfer-weighted images. The two masses were all surgically resected. The postoperative pathology indicated extranodal marginal zone B-cell lymphoma of MALT. To improve awareness of intracranial MALT lymphoma in the differential diagnosis of extra-axial lesions among clinicians, we present this report and briefly summarize previously reported cases to describe the clinical, pathological, radiological, and treatment features.