Nondilated obstructive uropathy and renal failure as a result of carcinoma of the intrapelvic area.

Renal failure secondary to obstruction of the urinary tract can sometimes present with only minimal or even no dilatation of the proximal part of the urinary tract; this is especially true when a history of malignancy within the pelvic area exists. Approximately 4 per cent of the patients who present with renal failure because of obstructive uropathy do so with minimal or no dilatation. Of these, approximately 60 per cent are associated with an intrapelvic malignancy. When a patient with renal failure presents with the associated findings of an intrapelvic or retroperitoneal tumor, it is imperative that obstructive uropathy be ruled out, even in the absence of dilatation.