脳転移をきたした舌癌の1例

Central Nervous System Metastasis from Lingual Carcinoma: Report of a case

I．はじめに

　舌癌は本邦では令悪性腫瘍の0.45％と比較的稀な腫瘍であるが，その80.2％に遠隔転移が見られ，臓器別の転移頻度は肺が46.7％と最も多く，中枢神経系への転移は2.5％と報告されている^16）．しかし，舌癌の脳転移に関する報告は極めて少なく，われわれの収集し得た限りでは2例の報告があるに過ぎない^1,12）．今回われわれは肺転移を伴う舌癌の化学療法後，再発を認めないにもかかわらず脳転移をきたした症例の詳細を報告し若干の文献的考察を加える．

A rare case of lingual carcinoma which metastasized to the brain is reported. A 66-year-old man was referred to our department on April 23, 1991, with complaints of memory disturbance and mild left motor weakness of one month's duration. The patient had been discharged from the Department of Otolaryngology of our hospital 9 months before, after undergoing radical neck dissection and chemotherapy (THP, CDDP, PEP) for his lingual cancer with metastases to the cervical lymph nodes and the lung. On admission to our department, the patient complained of mild frontalgia. Neurological examination showed memory disturbance, change of character, mild left hemiparesis and urinary incontinence. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a well circumscribed mass in the right frontal lobe associated with midline shift toward the left. Systemic Gallium-67 scintigraphy demonstrated an abnormal uptake in the right frontal region, but no abnormal uptake was seen in the neck and the lung. The most likely diagnosis was thought to be metastasis of lingual cancer. The patient underwent tumor removal 10 days after admission. A histological examination of the tumor specimen revealed metastatic anaplastic cell carci-noma, indicating a metastasis from lingual carcinoma. After postoperative radiotherapy (total 60 Gy), the pa-tient was discharged without neurological deficit. Central nervous system metastasis from lingual carci-noma is quite rare. To the best of our knowledge, only two such cases have been reported. We report another rare case of solitary brain metastasis from lingual carci-noma and review the pertinent medical literature.