A brain tumor misdiagnosed as dementia due to leukoencephalopathy-intravascular large B-cell lymphoma

Satoshi Utsuki, Sachio Suzuki, Kuniaki Nakahara, Sumito Sato, Hidehiro Oka, Kiyotaka Fujii

Department of Neurosurgery, Kitasato University School of Medicine

    Intravascular large B-cell lymphoma (IVLBCL) is a rare disease.  The diagnosis of IVLBCL is often delayed because it has non-specific clinical and imaging characteristics.  In fact, IVLBCL is rapidly progressive and is often diagnosed for the first time at autopsy.  Initially, IVLBCL is often diagnosed as Alzheimer's dementia, and then diagnosed as IVLBCL by subsequent brain biopsy, performed to further investigate the clinical features.
    The patient age range for IVLBCL is 64-82 years.  Between 3 and 7 months elapse exists before a brain biopsy is done after dementia is diagnosed.  On laboratory testing, the serum lactate dehydrogenase and soluble IL-2 receptor are elevated.  Examination of the cerebrospinal fluid reveals an increased cell count and elevated protein.  On magnetic resonance imaging of the head, a diffuse white matter lesion is shown.  The clinical manifestations improve for patients who receive chemotherapy immediately, but patients with delayed diagnoses rarely survive.
    IVLBCL has a low incidence, but it is necessary to establish the diagnosis by brain biopsy when IVLBCL is suspected because it is a treatable dementia.

Address correspondence to Dr. Satoshi Utsuki, Department of Neurosurgery, Kitasato University School of Medicine (1-15-1 Kitasato, Sagamihara, Kanagawa 228-8555, Japan)