脳に限局する"いわゆる網内系肉腫（Reticulosis）"の記録

TWO CASES OF "SO-CALLED RETICULUM CELL SARCOMA" (RETICULOSIS) IN THE BRAIN

I．はじめに

　脳に原発する肉腫の報告はBailey （1929）^1）にはじまる。ことに脳内の網内系に属する腫瘍（Microgliomaと称せられるものを含めて）の報告は，その稀少さ^2）3）—国内のそれは数例にすぎず，赤崎^4），高垣^5），都留^6），川淵7）ら—に加えて，この腫瘍を分類し命名するうえにたいせつなポイントを含むとみられる背景・組織由来についての論点に終始難渋さがただよい，この腫瘍の成り立ちへの解明が迂遠な道をたどつてきたかにみえる。私どもは，この数年間に1例の臨床例と，1例の剖検時，偶然に発見された大脳に原発する，あわせて2例の"いわゆる網内系肉腫"を経験する機会をもつた。それぞれ粗異なる予後を示したこの2つの腫瘍について理解の，なま硬さに当面して少なからずとまどつた。いま，この現状を記録にとどめたいと思う。

Two cases of "so-called reticulum cell sarcoma" of the brain were presented in detail, although the precise understanding of this tumor group is still controversial. A man of the first case (31-y-o. male) has been perfectly well for more than three years postoperatively. The material of the second case (78-y-o. male) was obtained from the autopsy of non-diagnosed case. Summarizing the literatures in short the criterion of the diagnosis of these tumors depends on the morphological metalophilicity to silver carbonate of parenchymal cells, with orwithout reticuline fibers ; tumor components having metalophilicity are described as microgliomata, while those having no metalophilicity but reticuline fibers, as reticulum cell sarcoma. The authers suggest from other point of view that the perivascular in the brain are the origin of these tumors, merely in the meaning of localization (perivascular space), but histogenetically these cells are thought to be monocytic reticular components. Since generally the correlation of the reticulum cells in the brain to reticuloendothelial system of the other parts of the body is not comprehensively understood, the brain tumor arising from the perivascular space is designated as reticulosis better than microgliomata. The other reason why these tumors are said as reticulosis, is based on the experimental grounds of autoradiographic findings presented by Konigsmark and Sidman (J. Neuropath. Exper. Neurol., 22: 643, 1963).