結石性膿腎症と鑑別が困難であった腎浸潤性移行上皮癌

Infiltrating transitional cell carcinoma of the kidney,hardly distinguished from calculous pyonephrosis：A case report

　腎浸潤性移行上皮癌は通常の腎盂移行上皮癌とは異なり，腎盂内に乳頭状発育をせず，腎実質内へ浸潤性に増殖する。今回，結石性膿腎症と鑑別困難であった症例を経験したので報告する。61歳，男性で，左側腹部痛，発熱，体重減少で来院した。X線写真で左腎結石と水腎症が認められ，尿所見で白血球多数，尿細胞診はclassⅡであった。逆行性腎盂造影では腎盂尿管移行部の狭窄が見られ，コンピュータ断層撮影法でも同部以上の腎盂尿管壁の肥厚が認められた。結石性腎盂腎炎と診断し，抗生剤投与を行ったが，解熱しなかった。経皮的腎砕石術（PNL）所見で腎盂粘膜は瘢痕化白色状で，隆起性病変は認めなかった。PNL後も解熱せず，結石性膿腎症と診断し，腎摘出術を行った。病理診断は腎浸潤性移行上皮癌であった。術後癌化学療法を行ったが播種性血管内凝固症候群（DIC）を併発し，術後49日目に死亡した。

A 61-year-old male visited our hospital,complaining of the left abdominal pain,high fever and weight loss. Urinary sediment contained many white blood cells,but no abnormal cells were found on cytology（classⅡ）. X-ray examination revealed a left renal stone（40×35mm）with hydronephrosis and ureteral stricture. CT showed a marked thickening of the ureter and the renal pelvic wall. PNL were performed and nephroscopic examination revealed scarred,ischemic white mucous membrane of the renal pelvis but no tumor mass. Since high fever continued even after PNL,left nephrectomy was performed. The kidney was firmly adhered to the surrounding tissues and pathologically diagnosed was infiltrating transitional cell carcinoma of the kidney. He developed DIC and died on the 49th postoperative day.