ダウン症候群に合併した頭蓋内胚細胞腫瘍の1例

Intracranial Germinoma Associated with Down Syndrome: Case Report and Review of Literature

Ⅰ．はじめに

　ダウン症候群（ダウン症）は21番染色体異常による先天性疾患であり，1,000人に1人の割合で発生する．多くの合併症が知られており，悪性腫瘍としては白血病が有名であるが，頭蓋内腫瘍の合併は稀である．また，合併する頭蓋内腫瘍の中では胚細胞性腫瘍の割合が多いとされているが，症例報告数としては少ない．今回われわれは，組織学的に胚腫と診断されたダウン症患者を経験したので報告する．

　It is well known that Down syndrome is sometimes associated with leukemia. However,there have been only a few case reports of a relationship between Down syndrome and brain tumors. The case was that of a 35-year-old man with Down syndrome complaining of gait disturbance. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a mass lesion in the pineal and bilateral cerebello-pontine cistern and spinal cord,marked hydrocephalus. Endoscopic biopsy and third ventriculostomy was performed. Surgical specimens showed typical germinoma. The patient was treated with a combination of chemotherapy with carboplatin and etposide,and irradiation. However he finally died 35 months after these therapies. Cases of malignant tumors other than leukemia,which are associated with Down syndrome,are extremely rare. We reviewed such rare cases of Down syndrome and intracranial germ cell tumor.