脳腫瘍に対する放射線治療後に発生した巨大な石灰化髄膜腫の1例

Giant Calcified Meningioma after Radiation Therapy : A case report

I．はじめに

　脳腫瘍の腫瘍内または腫瘍壁に数個から多数の大小不規則な石灰化がみられることは比較的多いが，腫瘍全体にわたり著明な石灰化（brain stone）が認められることは稀である．一方，放射線治療後に脳内に腫瘍を伴わない石灰化病変の症例報告は散見されるが^6,7,9），brain stoneが発生した症例についての報告はない．今回われわれは，放射線治療25年後に著明な石灰化を伴った巨大な髄膜腫が発生した1例を経験したので文献的考察を加えて報告する．

We presented a case of secondary giant meningioma with dense calcification (brain stone) after radiation ther-apy for primary ependymoma removed 25 years before.

A 31-year-old man was referred to our hospital be-cause of generalized convulsion. He had received extirpa-tion of an ependymoma in the left frontoparietal region and postoperative radiation therapy 25 years before. Skull X-ray and CT revealed a giant brain stone in the left parietal region. It was totally removed en bloc.Photomicrograph of the specimen showed proliferation of arachnoid cell-like tumor cells in narrow spaces sur-rounded by marked calcified lesions which showed partial ossification. The etiology and therapy of this tumor were discussed.