Dural Marginal Zone B Cell Lymphoma Presenting as a Non-traumatic Acute Epidural Hematoma: A Case Report.

Marginal zone B cell lymphoma, which can sometimes resemble a meningioma, originates in the dura mater. Reports of marginal zone B cell lymphoma complicated by intracranial hemorrhage are rare. There have been five reported cases of dural marginal zone B cell lymphoma complicated by acute subdural hematoma. To our knowledge, this is the first reported case of dural marginal zone B cell lymphoma diagnosed at the onset of a non-traumatic acute epidural hematoma. A 74-year-old man presented to our hospital with complaints of right hemiparesis without a history of head injury. He was diagnosed with left acute epidural hematoma based on the results of a computed tomography scan of the head; however, his serum soluble interleukin-2 receptor level was elevated (3,520 U/mL), and whole-body contrast-enhanced computed tomography revealed intra-abdominal and bilateral inguinal lymphadenopathy. Contrast-enhanced magnetic resonance imaging of the head revealed a well-enhanced, thickened dura mater with an acute epidural hematoma. The patient underwent a biopsy of the thickened dura mater and a hematoma removal, which on histopathology revealed dural marginal zone B cell lymphoma, as did a biopsy of an inguinal lymph node. After chemotherapy, the thickened dura mater shrank, and the marginal zone B cell lymphoma lesions showed remission. However, the mechanism underlying acute epidural hematoma in the dural marginal zone B cell lymphoma remains unclear. This case report provides new insights into dural marginal zone B cell lymphoma as a cause of non-traumatic acute epidural hematoma.