悪性黒色腫を併発したneurocutaneousmelanosisの1剖検例

AN AUTOPSY CASE OF NEUROCUTANEOUS MELANOSIS ASSOCIATED WITH INTRACEREBRAL MALIGNANT MELANOMA

　抄録　Neurocutaneous melanosisの1症例の臨床経過および剖検による病理組織学的所見についてその詳細を報告した。症例は13歳男子。生下時より全身に広汎な有毛性色素性母斑があり，13歳時に右前頭葉に悪性黒色腫を併発し，全経過6カ月にて死亡した。また加えて，先天性水晶体脱臼，性腺機能低下症，異所性前立腺管，停留睾丸，脊椎披裂，神経因性膀胱などの様々な合併症を有する稀な症例であった。過去の報告を渉猟し本邦例をまとめ検討を加えたところ，集計された35症例のうち男性例が28例を占め．発症に性差がみられた。皮膚病変の悪性化が明らかなもの2例に対し，脳軟膜においては28例（80％）が腫瘍性変化をきたしており，Ieptomeningeal melanosisに起因する痙攣発作や水頭症も加え，本疾患においては中枢神経病変がその予後を決定するものと考えられた。放射線治療は無効であるとの過去の記載に鑑み，手術による亜全摘を施行した後，現時点では悪性黒色腫に最も有効とされる制癌剤であるDTICによる化学療法を試みたが，治療効果は得られなかった。

The authors reported the clinical course and the postmortem examination of a unique case of neuro-cutaneous melanosis with numerous anomalies and complications, which included congenital dislocation of lenses, hypogonadism, ectopia of prostatic duct, genuine phimose, retentio testis, psina bifida and neurogenic bladder. This 13-year-old boy with a large hairy nevus in a bathing trunk configula-tion and multiple small nevi over the whole body since his birth was admitted to our hospital for evaluation of headache and vomiting. Neurological examination showed bilateral papilledema and slight left hemiparesis. A CT scan revealed a large right frontal mass and craniotomy was performed with subtotal removal of this tumor which was confirmed as a malignant leptomeningeal melano-ma. He initially made uneventful postoperative recovery, and two courses of chemothrapy with DTIC, ACNU and VCR were given ; however, the currence of brain tumor ensued shortly there-after, and he died in approximately six months after the onset of intracranial symptoms despite of the third course of chemotherapy.

Thirty five cases of neurocutaneous melanosis as-sociated with or without malignant melanoma have been reported in Japan. Twenty-eight cases were male and 7 female. Two cases showed the evidence of primary malignant melanoma outside of the cent-ral nervous system, whereas twenty eight leptome-ningeal melanoma, in which 22 were solid and 6 diffuse, were shown intracranially. Other 5 cases had epileptic seizure and/or hydrocephalus caused by wide spreaded leptmeningeal melanosis. This high incidence of intracranial malignant melanoma in this disorder was remarkable compaired with the previous reports in other countries. Mean duration between deaths and the onset of symptoms of intracranial hypertension or focal neurological signs was 7 months, ranging from 1 to 24 months, showing the rapidly deteriorating course in this disorder.

It has been suggested that irradiation to central nervous lesion is not effective, so we tried chemo-therapy including DTIC on our patient without any effect, rather complicated by intratumoral bleeding. It has been recommended by some au-thors that, if cerebral metastasis were present, DTIC therapy should not be given. The effectiveness of DTIC and other treatments on intracranial malig-nant melanoma is controversial, but the extremely poor prognosis of the cases with primary cerebral malignant melanoma requires further therapeutical evaluations earlier in the future.