髄上皮腫にみられる上衣芽，神経芽および海綿芽細胞などの混在について

On the mixture of ependymoblastic, neuroblastic and spongioblastic cells in the own and reported cases of medulloepithelioma

Ⅰ．緒言

　髄上皮腫（medulloepithelioma）が一つの独立したnosological entityとして認められるに至った経過は次の3期におよそ分けて考えることができる。

　すなわち第1期は，1926年，Bailey ＆ Cushing^2）が原始神経管に類似または相応する構造をもつ神経外胚葉腫瘍を髄上皮腫として初めて独立させ，gliomaの組織発生学的分類の中で最も未分化な腫瘍として位置づけた時期である。

In the present paper we performed a detailed histological examination on one autopsy case of medulloepithelioma occurred in the right temporal lobe of a 3-year-4-month-old boy, but also reevaluated by reference 10 previously reported cases of medulloepithelioma which had generally been accepted as such. In all of the previous reports the authors emphasized that their tumors were authentic medulloepitheliomas by illustrating portions of the so-called typical structure of the named tumor.