[A case of primary intracranial malignant lymphoma showing a spontaneous regression]

An eighty-year-old woman, who had been admitted with disorientation and gait disturbance, was revealed to have multiple intracranial tumors in the right temporal lobe and cerebellar vermis on CT and MRI. Following intravenous injection of dexamethasone (8 mg/day) for three days, isosorbide (90ml/day) was given in order to decrease brain edema, and the tumors increased in size rapidly in the next four months. However, most of the lesions disappeared or became markedly small without any specific therapy three months after the exacerbation of the disease. The brain tumors recurred one year thereafter, and the pathological diagnosis of primary intracranial malignant lymphoma, diffuse large B-cell type was done by autopsy examination. This patient was considered to have shown a spontaneous regression during the clinical course, and the clinicopathological descriptions of the case are presumed to present characteristic features of primary, intracranial malignant lymphoma.