脳内原発性細網肉腫の1症例

A CASE OF PRIMARY RETICULUM CELL SARCOMA OF THE CEREBRAL HEMISPHERE

Ｉ．緒言

　脳腫瘍に関する研究は，数多くみられるが，その対象は実験脳腫瘍をはじめ，glioma, meningioma, neurinomaなどの脳に頻発する腫瘍に限られ，その発生頻度の少ない肉腫に関する研究は数少ない。

　また，脳内に原発する肉腫群のなかでも，細網肉腫の発生は，きわめて稀なものである。

A case of primary reticulum cell sarcoma of the cerebral hemisphere is described.

The patient was a 41 years old Japanese female who was well till 21/2 months prior to her admission to our service when she started to have left sided hemiparesis. The examination on admission revealed complete left sided hemiplegia and marked papille-dema. From the right parietal lobe, a sharply circumscribed, grayish yellow mass approximately 3 cm in diameter was surgially removed. The histological examination of the surgical specimen was reported to be reticulum cell sarcoma. The patient expired 31/2 months after the surgery by recurrence of the neoplasm.

Post-mortem examination revealed a recurrent tumor mass at the site of operation with extensive infiltration to the opposite side of the cerebral hemisphere. No extracranial neoplastic lesion was found on autopsy.

On histological examination, it was an extremely malignant anaplastic neoplasm with closely packed cell which had little cytoplasm. The nuclei were large and mostly oval. Practically all nuclei had a heavy chromatin boundary. Mitotic figures were numerous (fig. 4, 5). The silver impregnation method for reticulum revealed varying amount of reticulin throughout the tumor (fig. 6, 7).