多発性脳出血にて発症した転移性悪性黒色腫の1例

A Case of Metastatic Malignant Melanoma Detected by Multifocal Cerebral Hemorrhage

Ⅰ．はじめに

　多発性脳出血にて発症した原発不明の転移性脳腫瘍に対して，外科的摘出術を行い，悪性黒色腫と診断された症例を経験した．悪性黒色腫は，白色人種に比べ，黒色人種や黄色人種では発生が少なく²⁷⁾，文献的にも日本では，人口10万人あたり1年間に1.5人と，欧米諸国に比べて低いと報告されている¹⁵⁾．このように，本邦での悪性黒色腫の発生率は少ないが，頭蓋内転移数は，全転移性脳腫瘍の1.5％を占め，7番目に多いとされている⁵⁾．今回経験した悪性黒色腫の脳転移症例について，文献的考察を踏まえ報告する．

　We encountered a case of intracranial metastatic malignant melanoma which caused repeated multiple hemorrhage. Intracranial metastatic malignant melanoma showed high intensity in the magnetic resonance imaging's T1 weighted image,low intensity in T2 weighted image and very low intensity in T2^＊ weighted image.

　Positron emission tomographic scans are useful for systemic evaluation of active malignancies. The present case underwent tumor removal following re-bleeding. The patient died of repeated hemorrhage one month after the operation.

　Intracranial metastatic malignant melanoma has a strong propensity to cause intracerebral hemorrhage leading to clinical deterioration.

　We think that the development of a therapeutic strategy for the treatment of intracranial metastatic malignant melanoma,including its risk management of intracerebral hemorrhage would be great importance.