[Malignant Lymphoma of the Brain, and Dementia].

A differential diagnosis of acute and subacute progressive dementias includes malignant lymphoma of the brain. We reviewed primary central nervous system lymphoma (PCNSL), intravascular lymphomatosis (IVL), lymphomatosis cerebri, and the relapse and invasion of systemic lymphomas. PCNSL is confined to the central nervous system; the infiltration and compression by the lymphoma result in adverse neurological symptoms. IVL is a rare form of malignant lymphoma that is characterized by the proliferation of primarily B-cell type lymphoma cells within the blood vessels of various organs. This causes ischemia and results in the associated neurological symptoms. Medical history and neuroimaging studies provide crucial informations to distinguish the lymphomas from other diseases that cause dementia, such an Alzheimer's disease. MRI imaging of the brain using contrast agent, and the biopsy of diseased tissues are essential for the diagnosis of the lymphomas. A histopathological examination is the most effective way to diagnose malignant lymphomas of the brain. Presently, the treatment of choice for PCNSL is the intravenous administration of high dose methotrexate with and without radiation therapy. Futhermore, Rituximab-containing chemotherapy has proved to greatly improve the prognosis of IVL. A better outcome can be achieved with the earlier diagnosis and treatment of the malignant lymphoma of the brain.