Astrocytoma治療後に著明なmetaplastic bone formationを伴うfibrosarcomaとglioblastomaの合併をみた一剖検例

CEREBRAL MIXED TUMOR:GLIOBLASTOMA:FIBROSARCOMA WITH METAPLASTIC BONE FORMATION

　抄録　頭蓋内悪性間葉性腫瘍の発生頻度は極めて低いものであるが，我々はastrocytomaに対する放射線治療後に発生した，著明なmetaplastic bone formationを伴うfibrosarcomaの1例を経験したので報告した。症例は37歳女性。左深側頭葉を中心にした腫瘍症例であり，第1回手術時組織診断はastrocy—toma G2であった。放射線治療約半年後，症状の進行がみられ，CT scanでは軽度石灰像を含む腫瘍の再発が認められた。第2回手術後（組織診断はglioblastoma） Ommaya’s reservoirよりβ—interferon腫瘍内投与を行ったが，CT scan上腫瘍は増大し，それと同時に石灰像の増加が認められた。剖検では，glioblastomaとfibrosarcomaの合併が認められた。fibrosarcomaの中には不規則な骨形成がみられ，骨芽細胞もみられたが，強い異形性はみられず，metaplastic bone formationと考えられた。

The authors report a case in which left deep temporal fibrosarcoma with calcified area develop-ed about 6 months after radiation therapy for left temporal astrocytoma.

A 37 year-old woman was admitted to our clinic because of headache and visual deterioration. CT scan and angiography suggested left deep temporal glioma and on August 5, 1980, partial resection was performed. Histological sections showed ast-rocytoma G 2. Postoperative course was uneventful and she left the hospital after radiation therapy of 50 Gy. On March, 1981, right hemiparesis wasnoticed and progressed rapidly. CT scan suggested left temporal tumor recurred. On March 30, 1981, second operation was performed and this time, histological sections showed glioblastoma. After operation, β-Interferon (IFN) was given intra-tumorally via Ommaya's reservoir (3×10⁶ IU, daily). But in spite of IFN therapy, tumor became larger and she died on June 30, 1981.

Autopsy revealed coexistence of glioblastoma and fibrosarcoma with metaplastic bone formation. A brief discussion concerning the problem of cerebral mixed tumors follows the description of the case.