延髄に発生したgangliogliomaの1例

Ganglioglioma of the Medulla Oblongata: Case Report and Review of the Literature

Ⅰ．はじめに

　Gangliogliomaは神経節細胞とグリア細胞の2種類の腫瘍化した細胞からなる比較的稀な腫瘍である．大部分はテント上に発生するが，約3％は脳幹に発生するとされる¹⁹⁾．約80％が30歳以下で発症し小児や若年成人に多い腫瘍であるが，頻度としては小児の中枢神経腫瘍の約4％，成人では約1.3％と報告されている^5,6,10,16)．基本的に発育緩徐な良性腫瘍であり，手術で全摘出することにより治癒が得られ予後は良好である⁹⁾．しかしテント上でも視床などの正中部や，脳幹部，脊髄では全摘が困難であるため再発が多く，また神経後遺症を残すことも少なくないとされる^8,11,12)．われわれは延髄全域から上部頸髄にかけて発生し非常に治療困難であったgangliogliomaの1例を経験したので報告する．

　The authors present a pediatric case of ganglioglioma occurring in the medulla oblongata. A 7-year-old boy was referred to our hospital with complaints of ataxia,seizure and sleep apnea. MRI of the brain disclosed a large tumor occupying the medulla oblongata,and the upper portion of the cervical spinal cord was also involved. The patient underwent midline suboccipital craniotomy and laminectomy of C1 to attempt radical resection of the tumor,which resulted only in partial removal of the tumor due to severe bradycardia during the operation. The histological diagnosis was ganglioglioma,WHO grade 2. Although both radiotherapy and chemotherapy were performed following the operation,the tumor remained unchanged. The patient died of respiratory arrest five months after the operation. Gangliogliomas usually occur in the supratentorial region,which permits easy surgical access and good prognosis. Only 3％ of gangliogliomas occur in the brain stem,and its management can be challenging because of the difficulty of radical resection and poor response to both radiotherapy and chemotherapy.