髄膜癌腫症の症状緩和に腰椎─腹腔シャント術が奏功した1例―圧可変バルブの使用について

A Case of Lumboperitoneal Shunt as an Effective Palliative Tool in a Patient with Leptomeningeal Metastasis

Ⅰ．はじめに

　新しい抗癌剤の登場で，進行癌に対する治療成績が向上している．また，ガンマナイフに代表される定位放射線治療により，生活の質（quality of life：QOL）を保ちつつ生存期間がのびている．癌患者の生存期間の延長に伴い，髄膜癌腫症に遭遇する機会が増えた．髄膜癌腫症の予後は今なお悪く，頭痛，嘔吐，意識障害などを合併するためQOLも低い．

　今回われわれは，肺癌を原発とする髄膜癌腫症に対して腰椎くも膜下腔─腹腔短絡（L-Pシャント）術を行い，術後頭痛が消失し劇的にQOLが改善した症例を経験した．癌性髄膜炎を伴った末期癌患者における症状緩和の有効な手段と考え報告する．また，この種の髄液シャント手術における圧可変バルブの使用法についても言及する．

　A 64 year-old woman with a diagnosis of lung adenocarcinoma was admitted to our neurosurgical division in February, 2007, suffering from severe headache and dizziness. Systemic chemotherapy had been repeated for multiple metastases to the bone and cerebral cortex since 7 months before. Reexamination with MRI revealed mild hydrocephalus without cortical metastasis. Cytological analysis of the cerebrospinal fluid (CSF) provided the diagnosis of leptomeningeal metastasis. Removal of 8 ml of CSF dramatically alleviated the patient's symptoms. To improve the quality of her remaining life, she underwent lumboperitoneal (L-P) shunt using a Strata^® adjustable pressure valve. Severe headache disappeared and other symptoms gradually improved after the operation. She survived for 10 months after the shunt placement, perticipating in family life for 6 months. Pressure level of the Strata^® valve was changed twice according to the degree of hydrocephalus and functioned well while her life lasted. The present case showed that L-P shunt is one of the effective palliative procedures and an adjustable pressure valve is available for this kind of CSF shunt in patients with leptomeningeal metastasis.