肺癌の硬膜転移により硬膜外血腫を呈した1例

A Case of Epidural Hematoma clue to Dural Metastasis

I．はじめに

　悪性腫瘍の硬膜転移に起因する頭蓋内血腫は，慢性硬膜下血腫例^{1,3,6,8-11,13,15-18）}は散見されるが，硬膜外血腫例^2）は，われわれが検索しえたかぎりでは，わずか1例にすぎない．われわれは，肺癌の頭蓋内転移摘出術後約1ヵ月目に，異なる部位の硬膜転移巣からの出血により硬膜外血腫を来たした1例を経験したので報告する．

Abstract

A case of epidural hematoma due to dural metastasis is reported.

A 62-year-old man was admitted to our hospital with generalized convulsion. A month prior, he underwent a tumor-removal operation for dural metastasis of lung cancer. CT scan on admission showed an epidural hematoma at the left frontal region. At operation, the epidural hematoma and dural invasion of neoplasm was found and removed. Pathological examination revealed dural metastasis of the poorly differentiated adenocarci-noma. According to the literature, intracranial metasta-sis of a hronchogenic carcinoma bleeds more often than that of other carcinomas. The particular vascular in-vasiveness of the neoplasm or a hemorrhagic diathesis is considered as the cause of the hemorrhage. In the present case the pathogenesis of the hemorrhage was thought to be the hypervascularity of the rapid growth tumor, fragility of the tumor vessels, and invasiveness of the tumor into the dural vessels. Adding to these, two other factors could play an important role in form-ing epidural hematoma ; 1) the tumor existed mainly in the epidural surface and 2) dural adhesion of the cra-nial bone was not so tight.