松果体部pure germinomaの治療8年後，腰仙椎硬膜外に転移を来した1例

A Case of Pineal Pure Germinoma Metastasized to the Lumbosacral Extradural Space 8 Years after Initial Therapy. Case Report and Review of Literature

Ⅰ．は じ め に

　頭蓋内germinomaが播種しやすいことは周知の事実であるが^{5,6,10,20,21)}，中枢神経系外へ転移を生じた例の報告も散見される^{2-14,16-18,22-24)}．今回われわれは，松果体部腫瘍の治療8年後，腰仙椎硬膜外に転移を来したpure germinomaの症例を経験したので，文献的考察を加え報告する．

　An 11-year-old boy first presented with a pineal tumor identified by neuroimaging but without positive serum or cerebrospinal fluid markers. The tumor disappeared after the craniotomy and following cranial irradiation. The pathologic diagnosis of the tumor was of a pure germinoma. Eight years later he returned to the hospital with spinal epidural metastasis from the pineal germinoma and required surgery. Intraoperative findings showed that the spinal tumor was solitarily located in the epidural space. Pathologically the tumor was a pure germinoma metastasis. He was treated by a combination of whole spinal irradiation and chemotherapy. The tumor disappeared after the therapy.

　A pineal germinoma occasionally disseminates through the ventricular system and spinal subarachnoid region. However,a solitary spinal epidural metastasis from pineal germinoma has rarely been reported. Regarding the route of this metastasis,we speculate that the CSF dissemination of the germinoma cells occurred first and some of those cells were trapped in the spinal nerve sleeve and extended into the epidural space.