Arterial graft to treat ruptured distal middle cerebral artery aneurysms in a patient with mucosa-associated lymphoid tissue lymphoma. Case report.

A 60-year-old man was admitted to our hospital with sudden onset of motor aphasia, Gerstmann syndrome, and incomplete right hemiparesis one week after administration of chemotherapy for mucosa-associated lymphoid tissue (MALT) lymphoma. Computed tomography showed an intracerebral hematoma in the left subcortical area. Cerebral angiography revealed 2 aneurysms on the distal middle cerebral artery (MCA) that increased in size in the course of 2 weeks. The aneurysms were excised and a bypass placed using a superficial temporal artery (STA) graft. Histological study showed no bacteria, infiltration of inflammatory cells, or lymphoma cells in the aneurysm wall. The chemotherapy against MALT lymphoma was highly effective, so we presumed that the lymphoma cells had disappeared. The source of the distal MCA aneurysms was thought to be oncotic. Distal MCA aneurysms caused by MALT lymphoma are extremely rare. Surgical reconstruction using the STA may be effective in patients with ruptured distal MCA aneurysms if the wall is intact.