原発性限局性膀胱アミロイドーシスの1例

Abstract

A case of primary localized amyloidosis of the bladder in a 63-year-old man is described. The initial symptom was painless gross haematuria. Cystoscopy revealed a solid, elevated and "beefy" tumor with haemorrhage in the right lateral wall of the bladder near the right ureteral orifice. An excretory urogram showed moderate right upper urinary tract dilatation. Pelvic arteriography showed a small hypervascularized area on the right side of the bladder. As in the majority of previous-reported cases, carcinoma was highly suspected, and transurethral biopsy with resection and fulguration of the lesion was therefore performed. Histologically, the biopsied specimen showed deposition of amyloid material mainly in the tunica propria and the absence of any carcinoma or specific inflammatory findings. Electron microscopic examination proved the existence of amyloid fibril. Serum electrophoresis pattern showed a normal pattern and urinary Bence-Jones protein was negative. Rectal biopsy revealed no amyloid deposits in the rectal wall. By these examinations, generalized, primary or secondary, amyloidosis were excluded. The remaining amyloid tumor of the bladder was thoroughly resected and fulgurated transurethrally. After the second resection, haematuria stopped and the dilatation of right upper urinary tract was improved. Primary localized amyloidosis of the bladder is rare and only 3 cases are reported in the domestic literature. Our case seems to be the fourth case in Japan.