[Primary spinal intramedullary malignant lymphoma: case report].

We report a case of primary spinal intramedullary malignant lymphoma. A 48-year-old man suffered from numbness and weakness of the left leg for 8 months. He was admitted to the hospital with progressive paraplegia and sudden onset of urinary retention. MRI revealed a low intensity mass on T1-weighted image with diffuse enhancement by Gd-DTPA in the thoracic spinal cord. An intramedullary spinal cord tumor was suspected and an urgent laminectomy (C7-Th5) was performed for decompression and confirmation. In the operation, the spinal cord was seen to be diffusely swollen, but no apparent tumor was identified either in color or consistency, and only biopsy was performed. The pathological diagnosis was malignant lymphoma (diffuse medium size-cell type). Investigations excluded the presence of lymphoma in other sites in the central nervous system and in the extraneural organs. We diagnosed a primary spinal intramedullary malignant lymphoma. Postoperative irradiation and chemotherapy were performed. After the irradiation with 16Gy to the tumor and 30Gy to the whole spinal axis, the tumor disappeared on MRI. One month later MRI demonstrated two markedly enhanced lesions in the right frontal lobe white mantle and the corpus callosum. He died of progressive respiratory disturbance 15 months after the beginning of his illness. Primary involvement of the spinal cord in malignant lymphoma is rare. Only 12 cases have been reported. The number of cases of malignant lymphoma in the central nervous system has gradually increased and it must be taken into consideration when diagnosing spinal cord tumors. We are looking forward to developing curative means including chemotherapy and radiotherapy.