Intrasellar Pure Germinomaの1例

A Case of Intrasellar Pure Germinoma

I．はじめに

　Germ cell tumorは鞍上部に好発することは周知の事実であるが，稀にトルコ鞍内発生，またはトルコ鞍内への発育進展がみられ，intrasellar germ cell tumorとして報告例が散見される^{1-7，9，10）}．

　特に，トルコ鞍内に発育するintrasellar germi-noma（以下IG）はCT，MRI上均一な内部構造と増強効果がみられpituitary adenomaとの鑑別が困難な例が多い^9）．われわれは，neurohypophysisに発生しトルコ鞍内への発育進展をみたintrasel-lar pure germinomaを経蝶形骨洞手術にて摘出し，5カ月後にテント上硬膜下腔に播種を来たした症例を経験した．本例について，発生母地とIGの臨床的特徴について若干の考察を加え報告する．

A 19-year-old male presented with progressive loss of vision and diabetes insipidus due to an intra-and suprasellar tumor. Transsphenoidal exploration revealed a pure germinoma. Seven days after the operation, bleeding from the residual tumor caused headache and right occulomotor palsy. The residual tumor and hematoma were removed using pterional approach. The residual tumor disappeared after postoperative irradiation. After 5 months of radiation, multiple lesions due to dissemination of the germinoma were dis-coverd in the suprasellar region. Adjuvant chemotherapy and whole supratentorial irradiation were per-formed. All lesions regressed completely. Mid-sagittal magnetic resonance image was useful in our patient for differential diagnosis between in-trasellar germinoma and pituitary adenoma. Before initiating an operation for intrasellar germinoma, awareness is needed for the fact of postoperative bleeding. We notice that transsphenoidal surgery should be selected for treatment of postoperative bleeding from intrasellar germinoma.