Methotrexate大量療法にて寛解後，乳房転移を来した中枢神経原発悪性リンパ腫の1例

A Case of Central Nervous System Lymphoma and Metastasized to Breast after Remission by Methotrexate Chemotherapy

Ⅰ．はじめに

　本症例は中枢神経原発非ホジキン悪性リンパ腫で，いったん完全寛解が得られたが約2年後に乳房転移を生じ，最終的には脳内局所再発で死亡した患者である^4,8)．節性リンパ腫と節外性リンパ腫では臨床経過，形態的，免疫学的特徴が異なり，臓器特異的悪性リンパ腫としての特殊性を認識することが重要となってきている．特に中枢神経原発悪性リンパ腫の予後は節外性リンパ腫の中で最も予後不良であり，本症例を通じて，中枢神経原発悪性リンパ腫の再発後の治療の難しさについて報告する．

We report a case of primary central nervous system lymphoma (PCNSL) who responded well to initial systemic chemotherapy, but subsequently developed breast metastasis with local recurrence in the brain 27 months after complete remission. The 53-year-old female suddenly felt weakness in her left extremity. She was transferred to the emergency ward in our hospital. Neurological examination on admission showed disorientated state and mild hemiparesis. Brain MRI showed a well enhanced round lesion in the right basal ganglia with perifocal edema. A stereotactic biopsy of the tumor made a diagnosis of classic diffuse non-Hodgkin's B-cell type lymphoma. She received chemotherapy with a high-dose methotrexate under a condition of 20％ of Karnofsky Performance Status (KPS). She enjoyed a useful life for about 5 years (KPS ; 60～70％). Both recurrent and metastatic lesions responded poorly to various aggressive multiagent regimens of chemotherapy. An intensive initial treatment for the primary lesion and closely monitoring of the whole body at regular intervals are necessary for ensuring a long useful life.