尿膜管癌による転移性脳腫瘍

Metastatic Brain Tumor from Urachal Cancer:A Case Report

Ⅰ．はじめに

　尿膜管癌は尿膜管より発生し，膀胱癌全体の0.17〜0.7%という稀な腫瘍である^2,5)．本疾患は，臨床症状に乏しいために診断まで時間がかかることや，局所浸潤傾向が強いことから予後不良な疾患である¹⁾．遠隔転移は晩期になるまでみられず¹⁰⁾，脳転移症例の報告は極めて少ない^5,11)．

　今回われわれは，脳転移発症で尿膜管癌が原発と診断された症例を経験したので，文献的考察を加えて報告する．

　Urachal cancers usually do not metastasize until the late stages, and local invasion and recurrence are observed with high frequency. We report a rare case of brain metastasis from urachal cancer in a 67-year-old female. She presented with abnormal behavior and right hemiparesis that started one month previously. MRI revealed a 55-mm lesion in the left frontal lobe, 5-mm in the right parietal lobe, and 2-mm lesion in the left cerebellum. The tumors showed ring enhancement on gadolinium-enhanced T1WI and were suspected to be metastatic brain tumors. Craniotomy was performed to excise the biggest tumor;the histological diagnosis was a poorly differentiated adenocarcinoma. As a result of the search for the primary tumor, the urachal carcinoma and multiple lung metastases were found. The patient chose best supportive care after diagnosis and died due to progression of multiple systemic metastases five months after surgery.