異なる臨床病理像をもつ多発性髄膜腫の1例

A Case of Multiple Meningiomas: Two Lesions have Different Clinicopathological Features, Respectively

Ⅰ．はじめに

　多発性髄膜腫は1938年にCushingとEisenhardtによって詳細に報告され⁸⁾，CTやMRIなど画像技術の発達によりその発見の割合は増加している^15,21)．多発性髄膜腫は画像上，大きさの異なる髄膜腫が両側大脳半球の円蓋部に存在することが多い¹³⁾．一方，髄膜腫は他の脳実質内の腫瘍にくらべ浮腫を生じる頻度は少ないといわれている^1,6)．今回われわれは，画像上ほぼ同じ大きさにもかかわらず，1病変のみが腫瘍周囲の著明な脳浮腫を伴っていた多発性髄膜腫の1症例を経験した．本症例に対し両側病変の摘出術を行い，病理学的検討を行ったところ，組織型や免疫染色所見など興味深い所見を認めたので，若干の文献的考察を加えて報告する．

　A 60-year-old man presented with general convulsion. Computed tomographic (CT) scans and magnetic resonance (MR) imaging showed two meningiomas located at the bilateral frontal convex respectively. In spite of the similar tumor size, the left tumor only had marked peritumoral edema. Angiography showed that the left lesion was more amply supplied from the internal carotid artery than the right one was. These two tumors were totally resected. The left tumor adhered to the surrounding brain tissue more intensely than the right one. Both tumors were microscopically diagnosed as angiomatous meningioma. The left tumor cells have a stronger immunopositivity for VEGF than the right ones. We suggest that pial-blood supply, adhesion to brain tissue and VEGF expression influence the development of meningioma-associated peritumoral edema.