[Spontaneous renal rupture caused by renal pelvic tumor: a case report].

A case of spontaneous rupture of the right kidney caused by a primary renal pelvic tumor is reported. A 57-year-old man complaining of right flank pain and gross hematuria was referred to our hospital in November 1992. In 1982, transurethral resection of the bladder tumor (TUR-Bt) and vesical instillation with mitomycin-C (MMC) had been performed at another hospital for recurrent bladder tumor. In 1988, the excretory urogram showed right hydronephrosis in the absence of a bladder tumor. In 1992, the excretory urogram revealed nonvisualization of the right kidney and obscurity of the right psoas muscle shadow. On the retrograde pyelogram, the upper calyx was irregular and the middle and lower calices were not clearly visualized. Selective renal arteriography demonstrated loss of continuity between the middle portion and lower poles. Right nephroureterectomy with bladder cuff was performed. The severely dilated pelvis contained a large amount of coagula and a papillary tumor. The thin renal parenchyme was lacerated at the lower pole. Histopathological findings revealed noninvasive transitional cell carcinoma. The present case represents the 6th spontaneous renal rupture caused by a renal pelvic tumor reported in Japan.