特異な頭蓋転移を呈した小児下肢原発横紋筋肉腫の1例

A Case of Brain Metastasis of Rhabdomyosarcoma in a Child

I．はじめに

　転移性脳腫瘍のなかで肉腫の脳転移は極めて稀で1.4％と報告されている^1）．

　われわれは，小児の下肢原発横紋筋肉腫の全身転移例を経験したが，頭部においてその転移形式が極めて特異的と思われたので若干の文献的考察を加えて報告する．

Abstract

We report here a specific case of metastatic brain tumor orienting from rhabdomyosarcoma.

An 11-year-old boy came to our hospital with com-plaints including headache, exophthalmos and tumors in the right frontal and left occipital region. 6 months previously subtotal removal of rhabdomyosarcoma in his right foot had been performed.

CT scan demonstrated tumors in the right orbit, right frontal region and left occipital region. The tumors ex-isted bilaterally in the skull and markedly enhanced by contrast medium (Fig. 1) . But the changes of the cra-nium were mild, only the diploe was slightly dilated. MRI showed that the tumors were extraaxial masses (Fig. 2). Right external carotid angiogram revealed numerous tumor vessels fed by the meningeal artery. On April 3rd, biopsy was performed at the right frontal region. The tumor had spread in the epidural space but the cortical surface seemed to be intact. His-tologically, the tumor consisted of small round cells and revealed multinucleal giant cells. It involved the skull bone, duramater and subdural tissues (Fig. 4) . Accor-dingly the tumor was diagnosed as rhabdomyosarcoma. Although tumor increased rapidly, the intracranial re-gion did not change remarkably. It was an interesting phenomenon. Eventually, rhabdomyosarcoma metasta-sized to the lung, and the patient died due to respira-tory distress.