IGF-Ⅱを産生した膀胱悪性孤在性線維性腫瘍（malignant solitary fibrous tumor）

Malignant solitary fibrous tumor of the urinary bladder with production of IGF-Ⅱ

59歳の男性が排尿障害を主訴に当科を受診した。超音波検査およびCTでは，膀胱壁から後腹膜腔に進展した直径13cm大のSOLを認めた。腫瘍切除および膀胱部分切除術を行い，病理診断はmalignant solitary fibrous tumorであった。腫瘍は10か月後に再発し，2度目の手術を行った。術前，患者は低血糖によるふざけ症状を呈した。低血糖の原因は腫瘍によるIGF-Ⅱ（immuno growth factor-Ⅱ）の異常分泌と考えられた。

A fifty-nine-year old man was referred to our department because of voiding difficulty. Ultrasound and computed tomography demonstrated a mass 13 cm in diameter located at the bladder wall extending to the retroperitoneal cavity. Excision of the tumor and partial cystectomy were performed. Histologic diagnosis was solitary fibrous tumor with malignant component. Ten months after the first surgery,a second surgery was performed for the recurrent tumor. The tumors were diagnosed as malignant solitary fibrous tumor. Before the second surgery,the patient experienced hypoglycemia with neuroglycopenia. Abnormal production of IGF-Ⅱ（Immuno Growth Factor-Ⅱ）by the tumor was the cause of hypoglycemia.