外科的摘出および定位放射線治療が有用であった転移性滑膜肉腫の1例

A Case of Synovial Sarcoma with Brain Metastasis Treated with Surgical Resection and Stereotactic Radiosurgery

Ⅰ．はじめに

　滑膜肉腫は若年成人の四肢近傍に好発する悪性軟部組織腫瘍であり，軟部肉腫の5～10%を占める疾患である．病理組織所見で滑膜に似た形態をとるため滑膜肉腫と命名されたが，起源は不明である．治療は広範囲切除が主軸であるが，5年生存率は36～82%と予後不良な疾患である．滑膜肉腫の約30%に転移を認めるが，頭蓋内転移は非常に稀であり，われわれの渉猟し得た限りでは過去に4例の報告がみられるのみである．

　今回われわれは，滑膜肉腫の転移性脳腫瘍の症例に対して外科的摘出および定位放射線治療を行い，良好な経過が得られたので，文献的考察を加え報告する．

　Synovial sarcomas compromise between 5 to 10% of all soft tissue sarcomas in adults. Synovial sarcoma commonly occurs in the vicinity of the large joints and cranial metastasis is rare. Here, we describe a case with intracranial metastases of a synovial sarcoma.

　A 41-year-old woman was admitted to our department with sensory aphasia. She had a history of a left inguinal synovial sarcoma and underwent surgery and chemotherapy for primary and metastatic lesions. Head MRI revealed three gadolinium-enhancing lesions in the left frontal, parietal and parietotemporal lobe. Gross total resection was achieved in the left parietotemporal lesion and pathological diagnosis was synovial sarcoma. Two weeks after surgery, she received cyber-knife radiosurgery and her neurological deficit was almost completely resolved. Intracranial metastatic synovial sarcoma is rare. Surgical resection and stereotaxic radiosurgery was very effective in the present case.