Occurrence of uroepithelial tumors of the upper urinary tract after the initial diagnosis of bladder cancer.

We treated 519 patients with primary bladder cancer, of whom 12 had upper urothelial tumor during followup. Almost all patients had superficial bladder cancer at diagnosis. All but 1 of 12 patients who underwent total cystectomy with ileal conduit diversion also underwent various transurethral procedures for treatment of the primary bladder lesions. The over-all incidence of bladder cancer patients who subsequently had upper urinary tract tumors was 2.3 per cent. Among the patients with treated bladder tumors a higher incidence (13.2 per cent) was observed in dye workers than in the general population (1.1 per cent). The interval between initial treatment of the bladder cancer and diagnosis of the upper urinary tract tumor ranged from 7 to 170 months (mean 70 months). The frequency of upper urinary tract tumors increased with time. We conclude that the appearance of upper urinary tract tumor after diagnosis of primary bladder cancer may be promoted by nonspecific irritation of the urothelium, which previously was made unstable by urinary chemical carcinogens.