[Case of intravascular lymphoma with a longitudinal spinal lesion diagnosed by multiple biopsies].

A 45-year-old man was admitted to our hospital with flaccid paraplegia. Neurological examination at a local hospital, 2 months before admission to our hospital, showed sensory impairment of the right posterior surface of the thigh and a decreased Achilles tendon reflex. Spinal magnetic resonance imaging (MRI) showed a T₂ weighted high-intensity area at the Th10-11 level that was more pronounced in the gray matter. The patient developed flaccid paraparesis and urinary retention. No improvement was observed after 2 rounds of methylprednisolone (mPSL) pulse therapy. Spinal cord biopsy showed demyelinated axons and myelinophagia without any tumorous lesion. Myelopathy exacerbated, and hence, plasma exchange was performed. However, this was ineffective. We suspected that myelopathy was caused by intravascular lymphoma (IVL) because of the presence of a low-grade fever, weight loss, and elevated serum soluble IL-2 receptor titers. Random biopsies, including skin, rectal, bone marrow, muscle, and renal biopsies, and splenectomy were performed to make a definite diagnosis of IVL myelopathy. Among these biopsies, the diagnosis of IVL myelopathy was confirmed from the renal specimen. The patient underwent chemotherapy at our hospital, and the IVL remitted. The results of this study confirm that sufficient systemic investigation by using tissue biopsy specimens should be performed in order to confirm the diagnosis of IVL myelopathy.