脊髄髄内原発悪性リンパ腫の1例

Primary Spinal Intramedullary Malignant Lymphoma:Case report

I．はじめに

　悪性リンパ腫が脊髄髄内に原発することはきわめて稀で，中枢神経原発悪性リンパ腫（CNS-ML）中の1％以下の発生率とされる^9）．われわれは上位胸髄髄内に原発し，治療後1カ月で頭蓋内再発の後，最終的には髄腔内播種を来たした悪性リンパ腫の1例を経験したので，若干の文献的考察を加え報告する．

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 in-tramedullary spinal cord tumor was suspected and an urgent laminectomy (C7-Th5) was performed for de-compression and confirmation. In the operation, the spinal cord was seen to be diffusely swollen, but no apparent tumor was identified either in color or con-sistency, and only biopsy was performed. The patholo-gical diagnosis was malignant lymphoma (diffuse medium size-cell type) . Investigations excluded the pre-sence 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 per-formed. After the irradiation with 16Gy to the tumor and 30Gy to the whole spinal axis, the tumor dis-appeared 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 pro-gressive respiratory disturbance 15 months after the be-ginning 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.