悪性変化をきたしたと考えられる上顎洞骨線維腫症例

OSTEOFIBROMA OF THE MAXILLARY SINUS THAT TURNED MALIGNANT

　Ⅰ．はじめに

　耳鼻咽喉科領域における良性腫瘍のうちで骨線維腫はさほど珍しい疾患ではない。しかし悪性化して肉腫を発生したという報告は本邦だけでなく外国の文献においても非常にまれである。われわれは13年前に右上顎洞の骨線維腫として治療を受け，その後再発もなく経過しながら最近骨肉腫の発生をみたまれな一症例を経験したので報告する。

　A case of osteosarcoma is reported. A man, aged 48, gave a history of having been treated for osteofibroma, elsewhere, 13 years ago and remained symptom-free until recently.

　Osteofibroma is generally considered as being benign, both, clinically and pathologically but, in rare cases it is also known to become malignant. The cause of this metamorphosis may be due to surgical intervention with partial removal, administration of irradiation treatment and intravenous anti-cancerous drugs or by local irritationfrom intraarterial injections. The osteofibroma may have an inherent tendency towards malignancy.