脊髄および脳幹部軟膜にびまん性に拡がつた脳脊髄軟膜肉腫（細網肉腫）の1剖検例

AN AUTOPSY CASE OF PRIMARY MENINGEAL SARCOMA DIFFUSELY INVOLVING THE LEPTOMENINGES OF SPINAL CORD AND BRAIN BASIS

I．はじめに

　頭蓋内腫瘍のなかで，脳脊髄軟膜にびまん性に拡がるものは一般に稀である^1）2）。そのような症例の多くは髄芽細胞腫などの神経膠腫が脳脊髄軟膜へ拡がつたものであるが，時には一般諸臓器の悪性腫瘍の脳脊髄軟膜転移による，いわゆる癌性あるいは肉腫性髄膜炎と呼ばれる病変に属するものもある。またごく稀には脳脊髄軟膜に肉腫が原発し，脳脊髄軟膜をびまん性におかすこともある。1902年Nonne^3）が脳脊髄軟膜のびまん性肉腫症の1例を報告して以来，類似の症例の報告がなされている^4）5）が，組織発生学的に必ずしも一致した見解は得られていないように思われる。

　わが国における原発性脳脊髄軟膜肉腫の報告はきわめて少ないようである^6）。われわれは，最近，脊髄から脳幹部の軟膜をびまん性におかした原発性脳脊髄軟膜細網肉腫の1剖検例を経験したのでその概要を報告したい。

A 55-year-old man complained of pain of his left arm in May 1966. Four months later, he was ad-mitted to the Kyushu University Hospital because of progressing pain of left arm, weakness of left limbs and sensory impairment of right lower limb. On ninth hospital day surgical treatment was done under the diagnosis of cervical cord tumor. Hard whitish tumor, 1 cm in diameter, was excised, which was histologically meningeal sarcoma. After this operation, quadriplegia, urinary incontinence and ter-minally unconsciousness were observed. He expired after eight months' duration of his illness and was autopsized.

Macroscopically, leptomeninges of spinal cord, brain stem, base of cerebellum and chiasm were dif-fusely thick and whitish in color. Several nodules as large as peas were detected at leptomeninges of cauda equina and right cerebellopontine angle. Sec-tioning of cerebellum, medulla oblongata and each level of spinal cord revealed irregularly invading tumorous mass from the leptomeninges into these sub-stances. Microscopically, tumor cells were polygonal in shape and each had a large clear nucleus with prominent nucleolus. Reticulin fibers much increased among the tumor cells.

From the above mentioned findings, this case was diagnosed as reticulum cell sarcoma originating from reticuloendothelial system of leptomeninges. And it was emphasized that reticulum cell sarcoma diffusely involving the leptomeninges was very rare in the literature.