成人に発生した両側視床神経膠腫の1例

Bilateral Thalamic Glioma in an Adult: A Case Report and Review of the Literature

Ⅰ．はじめに

　両側視床に発生する神経膠腫（bilateral thalamic glioma；以下BTG）は非常に稀な腫瘍であり，英語文献では小児34例，成人14例の報告があるのみである．過去の報告例を検討するとBTGの症例においては共通した初発症状や画像所見がみられ，また予後はおおむね不良である．今回われわれは成人に発生した両側視床星細胞腫を経験したので文献的考察を加えて報告する．

　We report a case of a 36-year-old woman who had a rare bilateral thalamic glioma (BTG). She complained of memory disorder. T1-weighted magnetic resonance imaging revealed enlarged bilateral thalami with homogenous isointensity and no contrast enhancement. Histological examination of the biopsy specimen identified diffuse astrocytoma (WHO gradeⅡ).

　BTG is a rare variant of thalamic neoplasms, which can be distinguished clinically and radiologically from other gliomas. In most of the reported cases, the presenting symptoms were cognitive impairment varying from personality changes to frank dementia. Death usually occurs within two years after onset, independently of adjuvant therapy such as radiotherapy and chemotherapy. On neuroimaging, all of the BTG had a similar appearance, with both thalami being symmetrically enlarged.

　Our patient has been given radiotherapy and concominant and adjuvant temozolomide in Stupp's regimen. At the time of this writing (5 months after the consultation), there are no neurological symptoms, and no changes on neuroimaging.